ccache: set base_dir

Codecov needs to see the token secret when uploading, so we have to
add this line to the workflow YAML:

```yaml
  with:
    token: ${{ secrets.CODECOV_TOKEN }}
```

Signed-off-by: Todd Gamblin <tgamblin@llnl.gov>

.github/workflows/build-containers.yml

@@ -40,17 +40,17 @@ jobs:
         # 1: Platforms to build for
         # 2: Base image (e.g. ubuntu:22.04)
         dockerfile: [[amazon-linux, 'linux/amd64,linux/arm64', 'amazonlinux:2'],
-                     [centos-stream9, 'linux/amd64,linux/arm64,linux/ppc64le', 'centos:stream9'],
-                     [leap15, 'linux/amd64,linux/arm64,linux/ppc64le', 'opensuse/leap:15'],
-                     [ubuntu-focal, 'linux/amd64,linux/arm64,linux/ppc64le', 'ubuntu:20.04'],
-                     [ubuntu-jammy, 'linux/amd64,linux/arm64,linux/ppc64le', 'ubuntu:22.04'],
-                     [ubuntu-noble, 'linux/amd64,linux/arm64,linux/ppc64le', 'ubuntu:24.04'],
-                     [almalinux8, 'linux/amd64,linux/arm64,linux/ppc64le', 'almalinux:8'],
-                     [almalinux9, 'linux/amd64,linux/arm64,linux/ppc64le', 'almalinux:9'],
+                     [centos-stream9, 'linux/amd64,linux/arm64', 'centos:stream9'],
+                     [leap15, 'linux/amd64,linux/arm64', 'opensuse/leap:15'],
+                     [ubuntu-focal, 'linux/amd64,linux/arm64', 'ubuntu:20.04'],
+                     [ubuntu-jammy, 'linux/amd64,linux/arm64', 'ubuntu:22.04'],
+                     [ubuntu-noble, 'linux/amd64,linux/arm64', 'ubuntu:24.04'],
+                     [almalinux8, 'linux/amd64,linux/arm64', 'almalinux:8'],
+                     [almalinux9, 'linux/amd64,linux/arm64', 'almalinux:9'],
                      [rockylinux8, 'linux/amd64,linux/arm64', 'rockylinux:8'],
                      [rockylinux9, 'linux/amd64,linux/arm64', 'rockylinux:9'],
-                     [fedora39, 'linux/amd64,linux/arm64,linux/ppc64le', 'fedora:39'],
-                     [fedora40, 'linux/amd64,linux/arm64,linux/ppc64le', 'fedora:40']]
+                     [fedora39, 'linux/amd64,linux/arm64', 'fedora:39'],
+                     [fedora40, 'linux/amd64,linux/arm64', 'fedora:40']]
     name: Build ${{ matrix.dockerfile[0] }}
     if: github.repository == 'spack/spack'
     steps:

.github/workflows/ci.yaml

@@ -81,6 +81,10 @@ jobs:
     with:
       with_coverage: ${{ needs.changes.outputs.core }}
 
+  import-check:
+    needs: [ changes ]
+    uses: ./.github/workflows/import-check.yaml
+
   all-prechecks:
     needs: [ prechecks ]
     if: ${{ always() }}

.github/workflows/coverage.yml

@@ -33,3 +33,4 @@ jobs:
       with:
         verbose: true
         fail_ci_if_error: false
+        token: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/import-check.yaml

@@ -0,0 +1,49 @@
+name: import-check
+
+on:
+  workflow_call:
+
+jobs:
+  # Check we don't make the situation with circular imports worse
+  import-check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: julia-actions/setup-julia@v2
+      with:
+        version: '1.10'
+    - uses: julia-actions/cache@v2
+
+    # PR: use the base of the PR as the old commit
+    - name: Checkout PR base commit
+      if: github.event_name == 'pull_request'
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+      with:
+        ref: ${{ github.event.pull_request.base.sha }}
+        path: old
+    # not a PR: use the previous commit as the old commit
+    - name: Checkout previous commit
+      if: github.event_name != 'pull_request'
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+      with:
+        fetch-depth: 2
+        path: old
+    - name: Checkout previous commit
+      if: github.event_name != 'pull_request'
+      run: git -C old reset --hard HEAD^
+
+    - name: Checkout new commit
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+      with:
+        path: new
+    - name: Install circular import checker
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+      with:
+        repository: haampie/circular-import-fighter
+        ref: e38bcd0aa46368e30648b61b7f0d8c1ca68aadff
+        path: circular-import-fighter
+    - name: Install dependencies
+      working-directory: circular-import-fighter
+      run: make -j dependencies
+    - name: Circular import check
+      working-directory: circular-import-fighter
+      run: make -j compare "SPACK_ROOT=../old ../new"

.github/workflows/valid-style.yml

@@ -86,66 +86,6 @@ jobs:
           spack -d bootstrap now --dev
           spack -d style -t black
           spack unit-test -V
-  # Check we don't make the situation with circular imports worse
-  import-check:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: julia-actions/setup-julia@v2
-      with:
-        version: '1.10'
-    - uses: julia-actions/cache@v2
-
-    # PR: use the base of the PR as the old commit
-    - name: Checkout PR base commit
-      if: github.event_name == 'pull_request'
-      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
-      with:
-        ref: ${{ github.event.pull_request.base.sha }}
-        path: old
-    # not a PR: use the previous commit as the old commit
-    - name: Checkout previous commit
-      if: github.event_name != 'pull_request'
-      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
-      with:
-        fetch-depth: 2
-        path: old
-    - name: Checkout previous commit
-      if: github.event_name != 'pull_request'
-      run: git -C old reset --hard HEAD^
-
-    - name: Checkout new commit
-      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
-      with:
-        path: new
-    - name: Install circular import checker
-      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
-      with:
-        repository: haampie/circular-import-fighter
-        ref: b5d6ce9be35f602cca7d5a6aa0259fca10639cca
-        path: circular-import-fighter
-    - name: Install dependencies
-      working-directory: circular-import-fighter
-      run: make -j dependencies
-    - name: Problematic imports before
-      working-directory: circular-import-fighter
-      run: make SPACK_ROOT=../old SUFFIX=.old
-    - name: Problematic imports after
-      working-directory: circular-import-fighter
-      run: make SPACK_ROOT=../new SUFFIX=.new
-    - name: Compare import cycles
-      working-directory: circular-import-fighter
-      run: |
-        edges_before="$(head -n1 solution.old)"
-        edges_after="$(head -n1 solution.new)"
-        if [ "$edges_after" -gt "$edges_before" ]; then
-          printf '\033[1;31mImport check failed: %s imports need to be deleted, ' "$edges_after"
-          printf 'previously this was %s\033[0m\n'  "$edges_before"
-          printf 'Compare \033[1;97m"Problematic imports before"\033[0m and '
-          printf '\033[1;97m"Problematic imports after"\033[0m.\n'
-          exit 1
-        else
-          printf '\033[1;32mImport check passed: %s <= %s\033[0m\n' "$edges_after" "$edges_before"
-        fi
 
   # Further style checks from pylint
   pylint:

bin/spack

@@ -25,7 +25,6 @@ exit 1
 # The code above runs this file with our preferred python interpreter.
 
 import os
-import os.path
 import sys
 
 min_python3 = (3, 6)

etc/spack/defaults/packages.yaml

@@ -36,7 +36,7 @@ packages:
       go-or-gccgo-bootstrap: [go-bootstrap, gcc]
       iconv: [libiconv]
       ipp: [intel-oneapi-ipp]
-      java: [openjdk, jdk, ibm-java]
+      java: [openjdk, jdk]
       jpeg: [libjpeg-turbo, libjpeg]
       lapack: [openblas, amdlibflame]
       libc: [glibc, musl]
@@ -73,15 +73,27 @@ packages:
     permissions:
       read: world
       write: user
+  cray-fftw:
+    buildable: false
+  cray-libsci:
+    buildable: false
   cray-mpich:
     buildable: false
   cray-mvapich2:
     buildable: false
+  cray-pmi:
+    buildable: false
   egl:
     buildable: false
+  essl:
+    buildable: false
   fujitsu-mpi:
     buildable: false
+  fujitsu-ssl2:
+    buildable: false
   hpcx-mpi:
     buildable: false
+  mpt:
+    buildable: false
   spectrum-mpi:
     buildable: false

lib/spack/docs/bootstrapping.rst

@@ -170,7 +170,7 @@ bootstrapping.
    To register the mirror on the platform where it's supposed to be used run the following command(s):
      % spack bootstrap add --trust local-sources /opt/bootstrap/metadata/sources
      % spack bootstrap add --trust local-binaries /opt/bootstrap/metadata/binaries
-
+     % spack buildcache update-index /opt/bootstrap/bootstrap_cache
 
 This command needs to be run on a machine with internet access and the resulting folder
 has to be moved over to the air-gapped system. Once the local sources are added using the

lib/spack/docs/build_systems/autotoolspackage.rst

@@ -272,9 +272,9 @@ often lists dependencies and the flags needed to locate them. The
 "environment variables" section lists environment variables that the
 build system uses to pass flags to the compiler and linker.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^
-Addings flags to configure
-^^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Adding flags to configure
+^^^^^^^^^^^^^^^^^^^^^^^^^
 
 For most of the flags you encounter, you will want a variant to
 optionally enable/disable them. You can then optionally pass these
@@ -285,7 +285,7 @@ function like so:
 
    def configure_args(self):
        args = []
-
+       ...
        if self.spec.satisfies("+mpi"):
            args.append("--enable-mpi")
        else:
@@ -299,7 +299,10 @@ Alternatively, you can use the :ref:`enable_or_disable  <autotools_enable_or_dis
 .. code-block:: python
 
    def configure_args(self):
-       return [self.enable_or_disable("mpi")]
+       args = []
+       ...
+       args.extend(self.enable_or_disable("mpi"))
+       return args
 
 
 Note that we are explicitly disabling MPI support if it is not
@@ -344,7 +347,14 @@ typically used to enable or disable some feature within the package.
        default=False,
        description="Memchecker support for debugging [degrades performance]"
    )
-   config_args.extend(self.enable_or_disable("memchecker"))
+   ...
+
+   def configure_args(self):
+       args = []
+       ...
+       args.extend(self.enable_or_disable("memchecker"))
+
+       return args
 
 In this example, specifying the variant ``+memchecker`` will generate
 the following configuration options:

lib/spack/docs/build_systems/custompackage.rst

@@ -56,13 +56,13 @@ If you look at the ``perl`` package, you'll see:
 
 .. code-block:: python
 
-   phases = ["configure", "build", "install"]
+   phases = ("configure", "build", "install")
 
 Similarly, ``cmake`` defines:
 
 .. code-block:: python
 
-   phases = ["bootstrap", "build", "install"]
+   phases = ("bootstrap", "build", "install")
 
 If we look at the ``cmake`` example, this tells Spack's ``PackageBase``
 class to run the ``bootstrap``, ``build``, and ``install`` functions

lib/spack/docs/contribution_guide.rst

@@ -361,7 +361,6 @@ and the tags associated with the class of runners to build on.
     * ``.linux_neoverse_n1``
     * ``.linux_neoverse_v1``
     * ``.linux_neoverse_v2``
-    * ``.linux_power``
     * ``.linux_skylake``
     * ``.linux_x86_64``
     * ``.linux_x86_64_v4``

lib/spack/docs/developer_guide.rst

@@ -543,10 +543,10 @@ With either interpreter you can run a single command:
 
 .. code-block:: console
 
-   $ spack python -c 'from spack.spec import Spec; Spec("python").concretized()'
+   $ spack python -c 'from spack.concretize import concretize_one; concretize_one("python")'
    ...
 
-   $ spack python -i ipython -c 'from spack.spec import Spec; Spec("python").concretized()'
+   $ spack python -i ipython -c 'from spack.concretize import concretize_one; concretize_one("python")'
    Out[1]: ...
 
 or a file:

lib/spack/docs/environments.rst

@@ -112,6 +112,19 @@ the original but may concretize differently in the presence of different
 explicit or default configuration settings (e.g., a different version of
 Spack or for a different user account).
 
+Environments created from a manifest will copy any included configs
+from relative paths inside the environment. Relative paths from
+outside the environment will cause errors, and absolute paths will be
+kept absolute. For example, if ``spack.yaml`` includes:
+
+.. code-block:: yaml
+
+   spack:
+     include: [./config.yaml]
+
+then the created environment will have its own copy of the file
+``config.yaml`` copied from the location in the original environment.
+
 Create an environment from a ``spack.lock`` file using:
 
 .. code-block:: console
@@ -160,7 +173,7 @@ accepts.  If an environment already exists then spack will simply activate it
 and ignore the create-specific flags.
 
 .. code-block:: console
-   
+
    $ spack env activate --create -p myenv
    # ...
    # [creates if myenv does not exist yet]
@@ -424,8 +437,8 @@ Developing Packages in a Spack Environment
 
 The ``spack develop`` command allows one to develop Spack packages in
 an environment. It requires a spec containing a concrete version, and
-will configure Spack to install the package from local source. 
-If a version is not provided from the command line interface then spack 
+will configure Spack to install the package from local source.
+If a version is not provided from the command line interface then spack
 will automatically pick the highest version the package has defined.
 This means any infinity versions (``develop``, ``main``, ``stable``) will be
 preferred in this selection process.
@@ -435,9 +448,9 @@ set, and Spack will ensure the package and its dependents are rebuilt
 any time the environment is installed if the package's local source
 code has been modified. Spack's native implementation to check for modifications
 is to check if ``mtime`` is newer than the installation.
-A custom check can be created by overriding the ``detect_dev_src_change`` method 
-in your package class. This is particularly useful for projects using custom spack repo's 
-to drive development and want to optimize performance. 
+A custom check can be created by overriding the ``detect_dev_src_change`` method
+in your package class. This is particularly useful for projects using custom spack repo's
+to drive development and want to optimize performance.
 
 Spack ensures that all instances of a
 developed package in the environment are concretized to match the
@@ -453,7 +466,7 @@ Further development on ``foo`` can be tested by re-installing the environment,
 and eventually committed and pushed to the upstream git repo.
 
 If the package being developed supports out-of-source builds then users can use the
-``--build_directory`` flag to control the location and name of the build directory. 
+``--build_directory`` flag to control the location and name of the build directory.
 This is a shortcut to set the ``package_attributes:build_directory`` in the
 ``packages`` configuration (see :ref:`assigning-package-attributes`).
 The supplied location will become the build-directory for that package in all future builds.

lib/spack/docs/module_file_support.rst

@@ -456,14 +456,13 @@ For instance, the following config options,
        tcl:
          all:
            suffixes:
-             ^python@3: 'python{^python.version}'
+             ^python@3: 'python{^python.version.up_to_2}'
              ^openblas: 'openblas'
 
-will add a ``python-3.12.1`` version string to any packages compiled with
-Python matching the spec, ``python@3``. This is useful to know which
-version of Python a set of Python extensions is associated with. Likewise, the
-``openblas`` string is attached to any program that has openblas in the spec,
-most likely via the ``+blas`` variant specification.
+will add a ``python3.12`` to module names of packages compiled with Python 3.12, and similarly for
+all specs depending on ``python@3``. This is useful to know which version of Python a set of Python
+extensions is associated with. Likewise, the ``openblas`` string is attached to any program that
+has openblas in the spec, most likely via the ``+blas`` variant specification.
 
 The most heavyweight solution to module naming is to change the entire
 naming convention for module files. This uses the projections format

lib/spack/env/cc

@@ -960,9 +960,6 @@ if [ -n "$SPACK_CCACHE_BINARY" ]; then
     case "$lang_flags" in
         C|CXX)  # ccache only supports C languages
             prepend full_command_list "${SPACK_CCACHE_BINARY}"
-            # workaround for stage being a temp folder
-            # see #3761#issuecomment-294352232
-            export CCACHE_NOHASHDIR=yes
             ;;
     esac
 fi

lib/spack/llnl/url.py

@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 """URL primitives that just require Python standard library."""
 import itertools
-import os.path
+import os
 import re
 from typing import Optional, Set, Tuple
 from urllib.parse import urlsplit, urlunsplit

lib/spack/llnl/util/filesystem.py

@@ -75,7 +75,6 @@
     "install_tree",
     "is_exe",
     "join_path",
-    "last_modification_time_recursive",
     "library_extensions",
     "mkdirp",
     "partition_path",
@@ -669,7 +668,7 @@ def copy(src, dest, _permissions=False):
         _permissions (bool): for internal use only
 
     Raises:
-        IOError: if *src* does not match any files or directories
+        OSError: if *src* does not match any files or directories
         ValueError: if *src* matches multiple files but *dest* is
             not a directory
     """
@@ -680,7 +679,7 @@ def copy(src, dest, _permissions=False):
 
     files = glob.glob(src)
     if not files:
-        raise IOError("No such file or directory: '{0}'".format(src))
+        raise OSError("No such file or directory: '{0}'".format(src))
     if len(files) > 1 and not os.path.isdir(dest):
         raise ValueError(
             "'{0}' matches multiple files but '{1}' is not a directory".format(src, dest)
@@ -711,7 +710,7 @@ def install(src, dest):
         dest (str): the destination file or directory
 
     Raises:
-        IOError: if *src* does not match any files or directories
+        OSError: if *src* does not match any files or directories
         ValueError: if *src* matches multiple files but *dest* is
             not a directory
     """
@@ -749,7 +748,7 @@ def copy_tree(
         _permissions (bool): for internal use only
 
     Raises:
-        IOError: if *src* does not match any files or directories
+        OSError: if *src* does not match any files or directories
         ValueError: if *src* is a parent directory of *dest*
     """
     if _permissions:
@@ -763,7 +762,7 @@ def copy_tree(
 
     files = glob.glob(src)
     if not files:
-        raise IOError("No such file or directory: '{0}'".format(src))
+        raise OSError("No such file or directory: '{0}'".format(src))
 
     # For Windows hard-links and junctions, the source path must exist to make a symlink. Add
     # all symlinks to this list while traversing the tree, then when finished, make all
@@ -844,7 +843,7 @@ def install_tree(src, dest, symlinks=True, ignore=None):
         ignore (typing.Callable): function indicating which files to ignore
 
     Raises:
-        IOError: if *src* does not match any files or directories
+        OSError: if *src* does not match any files or directories
         ValueError: if *src* is a parent directory of *dest*
     """
     copy_tree(src, dest, symlinks=symlinks, ignore=ignore, _permissions=True)
@@ -1470,15 +1469,36 @@ def set_executable(path):
 
 
 @system_path_filter
-def last_modification_time_recursive(path):
-    path = os.path.abspath(path)
-    times = [os.stat(path).st_mtime]
-    times.extend(
-        os.lstat(os.path.join(root, name)).st_mtime
-        for root, dirs, files in os.walk(path)
-        for name in dirs + files
-    )
-    return max(times)
+def recursive_mtime_greater_than(path: str, time: float) -> bool:
+    """Returns true if any file or dir recursively under `path` has mtime greater than `time`."""
+    # use bfs order to increase likelihood of early return
+    queue: Deque[str] = collections.deque([path])
+
+    if os.stat(path).st_mtime > time:
+        return True
+
+    while queue:
+        current = queue.popleft()
+
+        try:
+            entries = os.scandir(current)
+        except OSError:
+            continue
+
+        with entries:
+            for entry in entries:
+                try:
+                    st = entry.stat(follow_symlinks=False)
+                except OSError:
+                    continue
+
+                if st.st_mtime > time:
+                    return True
+
+                if entry.is_dir(follow_symlinks=False):
+                    queue.append(entry.path)
+
+    return False
 
 
 @system_path_filter
@@ -1740,8 +1760,7 @@ def find(
 
 
 def _log_file_access_issue(e: OSError, path: str) -> None:
-    errno_name = errno.errorcode.get(e.errno, "UNKNOWN")
-    tty.debug(f"find must skip {path}: {errno_name} {e}")
+    tty.debug(f"find must skip {path}: {e}")
 
 
 def _file_id(s: os.stat_result) -> Tuple[int, int]:

lib/spack/llnl/util/link_tree.py

@@ -308,7 +308,7 @@ class LinkTree:
 
     def __init__(self, source_root):
         if not os.path.exists(source_root):
-            raise IOError("No such file or directory: '%s'", source_root)
+            raise OSError("No such file or directory: '%s'", source_root)
 
         self._root = source_root
 

lib/spack/llnl/util/lock.py

@@ -391,7 +391,7 @@ def _poll_lock(self, op: int) -> bool:
 
             return True
 
-        except IOError as e:
+        except OSError as e:
             # EAGAIN and EACCES == locked by another process (so try again)
             if e.errno not in (errno.EAGAIN, errno.EACCES):
                 raise

lib/spack/llnl/util/tty/log.py

@@ -918,7 +918,7 @@ def _writer_daemon(
                         try:
                             if stdin_file.read(1) == "v":
                                 echo = not echo
-                        except IOError as e:
+                        except OSError as e:
                             # If SIGTTIN is ignored, the system gives EIO
                             # to let the caller know the read failed b/c it
                             # was in the bg. Ignore that too.
@@ -1013,7 +1013,7 @@ def wrapped(*args, **kwargs):
         while True:
             try:
                 return function(*args, **kwargs)
-            except IOError as e:
+            except OSError as e:
                 if e.errno == errno.EINTR:
                     continue
                 raise

lib/spack/spack/__init__.py

@@ -10,7 +10,7 @@
 import spack.util.git
 
 #: PEP440 canonical <major>.<minor>.<micro>.<devN> string
-__version__ = "0.24.0.dev0"
+__version__ = "1.0.0.dev0"
 spack_version = __version__
 
 

lib/spack/spack/audit.py

@@ -1356,14 +1356,8 @@ def _test_detection_by_executable(pkgs, debug_log, error_cls):
 
             def _compare_extra_attribute(_expected, _detected, *, _spec):
                 result = []
-                # Check items are of the same type
-                if not isinstance(_detected, type(_expected)):
-                    _summary = f'{pkg_name}: error when trying to detect "{_expected}"'
-                    _details = [f"{_detected} was detected instead"]
-                    return [error_cls(summary=_summary, details=_details)]
-
                 # If they are string expected is a regex
-                if isinstance(_expected, str):
+                if isinstance(_expected, str) and isinstance(_detected, str):
                     try:
                         _regex = re.compile(_expected)
                     except re.error:
@@ -1379,7 +1373,7 @@ def _compare_extra_attribute(_expected, _detected, *, _spec):
                         _details = [f"{_detected} does not match the regex"]
                         return [error_cls(summary=_summary, details=_details)]
 
-                if isinstance(_expected, dict):
+                elif isinstance(_expected, dict) and isinstance(_detected, dict):
                     _not_detected = set(_expected.keys()) - set(_detected.keys())
                     if _not_detected:
                         _summary = f"{pkg_name}: cannot detect some attributes for spec {_spec}"
@@ -1394,6 +1388,10 @@ def _compare_extra_attribute(_expected, _detected, *, _spec):
                         result.extend(
                             _compare_extra_attribute(_expected[_key], _detected[_key], _spec=_spec)
                         )
+                else:
+                    _summary = f'{pkg_name}: error when trying to detect "{_expected}"'
+                    _details = [f"{_detected} was detected instead"]
+                    return [error_cls(summary=_summary, details=_details)]
 
                 return result
 

lib/spack/spack/binary_distribution.py

@@ -5,6 +5,7 @@
 import codecs
 import collections
 import concurrent.futures
+import contextlib
 import copy
 import hashlib
 import io
@@ -23,7 +24,7 @@
 import urllib.request
 import warnings
 from contextlib import closing
-from typing import IO, Dict, Iterable, List, NamedTuple, Optional, Set, Tuple, Union
+from typing import IO, Callable, Dict, Iterable, List, NamedTuple, Optional, Set, Tuple, Union
 
 import llnl.util.filesystem as fsys
 import llnl.util.lang
@@ -91,6 +92,9 @@
 CURRENT_BUILD_CACHE_LAYOUT_VERSION = 2
 
 
+INDEX_HASH_FILE = "index.json.hash"
+
+
 class BuildCacheDatabase(spack_db.Database):
     """A database for binary buildcaches.
 
@@ -502,7 +506,7 @@ def _fetch_and_cache_index(self, mirror_url, cache_entry={}):
         scheme = urllib.parse.urlparse(mirror_url).scheme
 
         if scheme != "oci" and not web_util.url_exists(
-            url_util.join(mirror_url, BUILD_CACHE_RELATIVE_PATH, "index.json")
+            url_util.join(mirror_url, BUILD_CACHE_RELATIVE_PATH, spack_db.INDEX_JSON_FILE)
         ):
             return False
 
@@ -669,19 +673,24 @@ def sign_specfile(key: str, specfile_path: str) -> str:
 
 
 def _read_specs_and_push_index(
-    file_list, read_method, cache_prefix, db: BuildCacheDatabase, temp_dir, concurrency
+    file_list: List[str],
+    read_method: Callable,
+    cache_prefix: str,
+    db: BuildCacheDatabase,
+    temp_dir: str,
+    concurrency: int,
 ):
     """Read all the specs listed in the provided list, using thread given thread parallelism,
         generate the index, and push it to the mirror.
 
     Args:
-        file_list (list(str)): List of urls or file paths pointing at spec files to read
+        file_list: List of urls or file paths pointing at spec files to read
         read_method: A function taking a single argument, either a url or a file path,
             and which reads the spec file at that location, and returns the spec.
-        cache_prefix (str): prefix of the build cache on s3 where index should be pushed.
+        cache_prefix: prefix of the build cache on s3 where index should be pushed.
         db: A spack database used for adding specs and then writing the index.
-        temp_dir (str): Location to write index.json and hash for pushing
-        concurrency (int): Number of parallel processes to use when fetching
+        temp_dir: Location to write index.json and hash for pushing
+        concurrency: Number of parallel processes to use when fetching
     """
     for file in file_list:
         contents = read_method(file)
@@ -699,7 +708,7 @@ def _read_specs_and_push_index(
 
     # Now generate the index, compute its hash, and push the two files to
     # the mirror.
-    index_json_path = os.path.join(temp_dir, "index.json")
+    index_json_path = os.path.join(temp_dir, spack_db.INDEX_JSON_FILE)
     with open(index_json_path, "w", encoding="utf-8") as f:
         db._write_to_file(f)
 
@@ -709,14 +718,14 @@ def _read_specs_and_push_index(
         index_hash = compute_hash(index_string)
 
     # Write the hash out to a local file
-    index_hash_path = os.path.join(temp_dir, "index.json.hash")
+    index_hash_path = os.path.join(temp_dir, INDEX_HASH_FILE)
     with open(index_hash_path, "w", encoding="utf-8") as f:
         f.write(index_hash)
 
     # Push the index itself
     web_util.push_to_url(
         index_json_path,
-        url_util.join(cache_prefix, "index.json"),
+        url_util.join(cache_prefix, spack_db.INDEX_JSON_FILE),
         keep_original=False,
         extra_args={"ContentType": "application/json", "CacheControl": "no-cache"},
     )
@@ -724,7 +733,7 @@ def _read_specs_and_push_index(
     # Push the hash
     web_util.push_to_url(
         index_hash_path,
-        url_util.join(cache_prefix, "index.json.hash"),
+        url_util.join(cache_prefix, INDEX_HASH_FILE),
         keep_original=False,
         extra_args={"ContentType": "text/plain", "CacheControl": "no-cache"},
     )
@@ -793,7 +802,7 @@ def url_read_method(url):
         try:
             _, _, spec_file = web_util.read_from_url(url)
             contents = codecs.getreader("utf-8")(spec_file).read()
-        except web_util.SpackWebError as e:
+        except (web_util.SpackWebError, OSError) as e:
             tty.error(f"Error reading specfile: {url}: {e}")
         return contents
 
@@ -861,9 +870,12 @@ def _url_generate_package_index(url: str, tmpdir: str, concurrency: int = 32):
     tty.debug(f"Retrieving spec descriptor files from {url} to build index")
 
     db = BuildCacheDatabase(tmpdir)
+    db._write()
 
     try:
-        _read_specs_and_push_index(file_list, read_fn, url, db, db.database_directory, concurrency)
+        _read_specs_and_push_index(
+            file_list, read_fn, url, db, str(db.database_directory), concurrency
+        )
     except Exception as e:
         raise GenerateIndexError(f"Encountered problem pushing package index to {url}: {e}") from e
 
@@ -1777,7 +1789,7 @@ def _oci_update_index(
         db.mark(spec, "in_buildcache", True)
 
     # Create the index.json file
-    index_json_path = os.path.join(tmpdir, "index.json")
+    index_json_path = os.path.join(tmpdir, spack_db.INDEX_JSON_FILE)
     with open(index_json_path, "w", encoding="utf-8") as f:
         db._write_to_file(f)
 
@@ -1998,7 +2010,7 @@ def fetch_url_to_mirror(url):
 
                 # Download the config = spec.json and the relevant tarball
                 try:
-                    manifest = json.loads(response.read())
+                    manifest = json.load(response)
                     spec_digest = spack.oci.image.Digest.from_string(manifest["config"]["digest"])
                     tarball_digest = spack.oci.image.Digest.from_string(
                         manifest["layers"][-1]["digest"]
@@ -2125,10 +2137,9 @@ def fetch_url_to_mirror(url):
 
 
 def dedupe_hardlinks_if_necessary(root, buildinfo):
-    """Updates a buildinfo dict for old archives that did
-    not dedupe hardlinks. De-duping hardlinks is necessary
-    when relocating files in parallel and in-place. This
-    means we must preserve inodes when relocating."""
+    """Updates a buildinfo dict for old archives that did not dedupe hardlinks. De-duping hardlinks
+    is necessary when relocating files in parallel and in-place. This means we must preserve inodes
+    when relocating."""
 
     # New archives don't need this.
     if buildinfo.get("hardlinks_deduped", False):
@@ -2157,69 +2168,47 @@ def dedupe_hardlinks_if_necessary(root, buildinfo):
         buildinfo[key] = new_list
 
 
-def relocate_package(spec):
-    """
-    Relocate the given package
-    """
-    workdir = str(spec.prefix)
-    buildinfo = read_buildinfo_file(workdir)
-    new_layout_root = str(spack.store.STORE.layout.root)
-    new_prefix = str(spec.prefix)
-    new_rel_prefix = str(os.path.relpath(new_prefix, new_layout_root))
-    new_spack_prefix = str(spack.paths.prefix)
-
-    old_sbang_install_path = None
-    if "sbang_install_path" in buildinfo:
-        old_sbang_install_path = str(buildinfo["sbang_install_path"])
+def relocate_package(spec: spack.spec.Spec) -> None:
+    """Relocate binaries and text files in the given spec prefix, based on its buildinfo file."""
+    spec_prefix = str(spec.prefix)
+    buildinfo = read_buildinfo_file(spec_prefix)
     old_layout_root = str(buildinfo["buildpath"])
-    old_spack_prefix = str(buildinfo.get("spackprefix"))
-    old_rel_prefix = buildinfo.get("relative_prefix")
-    old_prefix = os.path.join(old_layout_root, old_rel_prefix)
 
-    # Warn about old style tarballs created with the now removed --rel flag.
+    # Warn about old style tarballs created with the --rel flag (removed in Spack v0.20)
     if buildinfo.get("relative_rpaths", False):
         tty.warn(
-            f"Tarball for {spec} uses relative rpaths, " "which can cause library loading issues."
+            f"Tarball for {spec} uses relative rpaths, which can cause library loading issues."
         )
 
-    # In the past prefix_to_hash was the default and externals were not dropped, so prefixes
-    # were not unique.
+    # In Spack 0.19 and older prefix_to_hash was the default and externals were not dropped, so
+    # prefixes were not unique.
     if "hash_to_prefix" in buildinfo:
         hash_to_old_prefix = buildinfo["hash_to_prefix"]
     elif "prefix_to_hash" in buildinfo:
-        hash_to_old_prefix = dict((v, k) for (k, v) in buildinfo["prefix_to_hash"].items())
+        hash_to_old_prefix = {v: k for (k, v) in buildinfo["prefix_to_hash"].items()}
     else:
-        hash_to_old_prefix = dict()
+        raise NewLayoutException(
+            "Package tarball was created from an install prefix with a different directory layout "
+            "and an older buildcache create implementation. It cannot be relocated."
+        )
 
-    if old_rel_prefix != new_rel_prefix and not hash_to_old_prefix:
-        msg = "Package tarball was created from an install "
-        msg += "prefix with a different directory layout and an older "
-        msg += "buildcache create implementation. It cannot be relocated."
-        raise NewLayoutException(msg)
+    prefix_to_prefix: Dict[str, str] = {}
 
-    # Spurious replacements (e.g. sbang) will cause issues with binaries
-    # For example, the new sbang can be longer than the old one.
-    # Hence 2 dictionaries are maintained here.
-    prefix_to_prefix_text = collections.OrderedDict()
-    prefix_to_prefix_bin = collections.OrderedDict()
+    if "sbang_install_path" in buildinfo:
+        old_sbang_install_path = str(buildinfo["sbang_install_path"])
+        prefix_to_prefix[old_sbang_install_path] = spack.hooks.sbang.sbang_install_path()
 
-    if old_sbang_install_path:
-        install_path = spack.hooks.sbang.sbang_install_path()
-        prefix_to_prefix_text[old_sbang_install_path] = install_path
+    # First match specific prefix paths. Possibly the *local* install prefix of some dependency is
+    # in an upstream, so we cannot assume the original spack store root can be mapped uniformly to
+    # the new spack store root.
 
-    # First match specific prefix paths. Possibly the *local* install prefix
-    # of some dependency is in an upstream, so we cannot assume the original
-    # spack store root can be mapped uniformly to the new spack store root.
-    #
-    # If the spec is spliced, we need to handle the simultaneous mapping
-    # from the old install_tree to the new install_tree and from the build_spec
-    # to the spliced spec.
-    # Because foo.build_spec is foo for any non-spliced spec, we can simplify
-    # by checking for spliced-in nodes by checking for nodes not in the build_spec
-    # without any explicit check for whether the spec is spliced.
-    # An analog in this algorithm is any spec that shares a name or provides the same virtuals
-    # in the context of the relevant root spec. This ensures that the analog for a spec s
-    # is the spec that s replaced when we spliced.
+    # If the spec is spliced, we need to handle the simultaneous mapping from the old install_tree
+    # to the new install_tree and from the build_spec to the spliced spec. Because foo.build_spec
+    # is foo for any non-spliced spec, we can simplify by checking for spliced-in nodes by checking
+    # for nodes not in the build_spec without any explicit check for whether the spec is spliced.
+    # An analog in this algorithm is any spec that shares a name or provides the same virtuals in
+    # the context of the relevant root spec. This ensures that the analog for a spec s is the spec
+    # that s replaced when we spliced.
     relocation_specs = specs_to_relocate(spec)
     build_spec_ids = set(id(s) for s in spec.build_spec.traverse(deptype=dt.ALL & ~dt.BUILD))
     for s in relocation_specs:
@@ -2239,72 +2228,66 @@ def relocate_package(spec):
         lookup_dag_hash = analog.dag_hash()
         if lookup_dag_hash in hash_to_old_prefix:
             old_dep_prefix = hash_to_old_prefix[lookup_dag_hash]
-            prefix_to_prefix_bin[old_dep_prefix] = str(s.prefix)
-            prefix_to_prefix_text[old_dep_prefix] = str(s.prefix)
+            prefix_to_prefix[old_dep_prefix] = str(s.prefix)
 
     # Only then add the generic fallback of install prefix -> install prefix.
-    prefix_to_prefix_text[old_prefix] = new_prefix
-    prefix_to_prefix_bin[old_prefix] = new_prefix
-    prefix_to_prefix_text[old_layout_root] = new_layout_root
-    prefix_to_prefix_bin[old_layout_root] = new_layout_root
+    prefix_to_prefix[old_layout_root] = str(spack.store.STORE.layout.root)
 
-    # This is vestigial code for the *old* location of sbang. Previously,
-    # sbang was a bash script, and it lived in the spack prefix. It is
-    # now a POSIX script that lives in the install prefix. Old packages
-    # will have the old sbang location in their shebangs.
-    orig_sbang = "#!/bin/bash {0}/bin/sbang".format(old_spack_prefix)
-    new_sbang = spack.hooks.sbang.sbang_shebang_line()
-    prefix_to_prefix_text[orig_sbang] = new_sbang
+    # Delete identity mappings from prefix_to_prefix
+    prefix_to_prefix = {k: v for k, v in prefix_to_prefix.items() if k != v}
 
-    tty.debug("Relocating package from", "%s to %s." % (old_layout_root, new_layout_root))
+    # If there's nothing to relocate, we're done.
+    if not prefix_to_prefix:
+        return
+
+    for old, new in prefix_to_prefix.items():
+        tty.debug(f"Relocating: {old} => {new}.")
 
     # Old archives may have hardlinks repeated.
-    dedupe_hardlinks_if_necessary(workdir, buildinfo)
+    dedupe_hardlinks_if_necessary(spec_prefix, buildinfo)
 
     # Text files containing the prefix text
-    text_names = [os.path.join(workdir, f) for f in buildinfo["relocate_textfiles"]]
+    textfiles = [os.path.join(spec_prefix, f) for f in buildinfo["relocate_textfiles"]]
+    binaries = [os.path.join(spec_prefix, f) for f in buildinfo.get("relocate_binaries")]
+    links = [os.path.join(spec_prefix, f) for f in buildinfo.get("relocate_links", [])]
 
-    # If we are not installing back to the same install tree do the relocation
-    if old_prefix != new_prefix:
-        files_to_relocate = [
-            os.path.join(workdir, filename) for filename in buildinfo.get("relocate_binaries")
-        ]
-        # If the buildcache was not created with relativized rpaths
-        # do the relocation of path in binaries
-        platform = spack.platforms.by_name(spec.platform)
-        if "macho" in platform.binary_formats:
-            relocate.relocate_macho_binaries(files_to_relocate, prefix_to_prefix_bin)
-        elif "elf" in platform.binary_formats:
-            # The new ELF dynamic section relocation logic only handles absolute to
-            # absolute relocation.
-            relocate.relocate_elf_binaries(files_to_relocate, prefix_to_prefix_bin)
+    platform = spack.platforms.by_name(spec.platform)
+    if "macho" in platform.binary_formats:
+        relocate.relocate_macho_binaries(binaries, prefix_to_prefix)
+    elif "elf" in platform.binary_formats:
+        relocate.relocate_elf_binaries(binaries, prefix_to_prefix)
 
-        # Relocate links to the new install prefix
-        links = [os.path.join(workdir, f) for f in buildinfo.get("relocate_links", [])]
-        relocate.relocate_links(links, prefix_to_prefix_bin)
+    relocate.relocate_links(links, prefix_to_prefix)
+    relocate.relocate_text(textfiles, prefix_to_prefix)
+    changed_files = relocate.relocate_text_bin(binaries, prefix_to_prefix)
 
-        # For all buildcaches
-        # relocate the install prefixes in text files including dependencies
-        relocate.relocate_text(text_names, prefix_to_prefix_text)
+    # Add ad-hoc signatures to patched macho files when on macOS.
+    if "macho" in platform.binary_formats and sys.platform == "darwin":
+        codesign = which("codesign")
+        if not codesign:
+            return
+        for binary in changed_files:
+            # preserve the original inode by running codesign on a copy
+            with fsys.edit_in_place_through_temporary_file(binary) as tmp_binary:
+                codesign("-fs-", tmp_binary)
 
-        # relocate the install prefixes in binary files including dependencies
-        changed_files = relocate.relocate_text_bin(files_to_relocate, prefix_to_prefix_bin)
+    install_manifest = os.path.join(
+        spec.prefix,
+        spack.store.STORE.layout.metadata_dir,
+        spack.store.STORE.layout.manifest_file_name,
+    )
+    if not os.path.exists(install_manifest):
+        spec_id = spec.format("{name}/{hash:7}")
+        tty.warn("No manifest file in tarball for spec %s" % spec_id)
 
-        # Add ad-hoc signatures to patched macho files when on macOS.
-        if "macho" in platform.binary_formats and sys.platform == "darwin":
-            codesign = which("codesign")
-            if not codesign:
-                return
-            for binary in changed_files:
-                # preserve the original inode by running codesign on a copy
-                with fsys.edit_in_place_through_temporary_file(binary) as tmp_binary:
-                    codesign("-fs-", tmp_binary)
+    # overwrite old metadata with new
+    if spec.spliced:
+        # rewrite spec on disk
+        spack.store.STORE.layout.write_spec(spec, spack.store.STORE.layout.spec_file_path(spec))
 
-    # If we are installing back to the same location
-    # relocate the sbang location if the spack directory changed
-    else:
-        if old_spack_prefix != new_spack_prefix:
-            relocate.relocate_text(text_names, prefix_to_prefix_text)
+        # de-cache the install manifest
+        with contextlib.suppress(FileNotFoundError):
+            os.unlink(install_manifest)
 
 
 def _extract_inner_tarball(spec, filename, extract_to, signature_required: bool, remote_checksum):
@@ -2472,15 +2455,6 @@ def extract_tarball(spec, download_result, force=False, timer=timer.NULL_TIMER):
     except Exception as e:
         shutil.rmtree(spec.prefix, ignore_errors=True)
         raise e
-    else:
-        manifest_file = os.path.join(
-            spec.prefix,
-            spack.store.STORE.layout.metadata_dir,
-            spack.store.STORE.layout.manifest_file_name,
-        )
-        if not os.path.exists(manifest_file):
-            spec_id = spec.format("{name}/{hash:7}")
-            tty.warn("No manifest file in tarball for spec %s" % spec_id)
     finally:
         if tmpdir:
             shutil.rmtree(tmpdir, ignore_errors=True)
@@ -2585,10 +2559,6 @@ def install_root_node(
         tty.msg('Installing "{0}" from a buildcache'.format(spec.format()))
         extract_tarball(spec, download_result, force)
         spec.package.windows_establish_runtime_linkage()
-        if spec.spliced:  # overwrite old metadata with new
-            spack.store.STORE.layout.write_spec(
-                spec, spack.store.STORE.layout.spec_file_path(spec)
-            )
         spack.hooks.post_install(spec, False)
         spack.store.STORE.db.add(spec, allow_missing=allow_missing)
 
@@ -2626,11 +2596,14 @@ def try_direct_fetch(spec, mirrors=None):
         )
         try:
             _, _, fs = web_util.read_from_url(buildcache_fetch_url_signed_json)
+            specfile_contents = codecs.getreader("utf-8")(fs).read()
             specfile_is_signed = True
-        except web_util.SpackWebError as e1:
+        except (web_util.SpackWebError, OSError) as e1:
             try:
                 _, _, fs = web_util.read_from_url(buildcache_fetch_url_json)
-            except web_util.SpackWebError as e2:
+                specfile_contents = codecs.getreader("utf-8")(fs).read()
+                specfile_is_signed = False
+            except (web_util.SpackWebError, OSError) as e2:
                 tty.debug(
                     f"Did not find {specfile_name} on {buildcache_fetch_url_signed_json}",
                     e1,
@@ -2640,7 +2613,6 @@ def try_direct_fetch(spec, mirrors=None):
                     f"Did not find {specfile_name} on {buildcache_fetch_url_json}", e2, level=2
                 )
                 continue
-        specfile_contents = codecs.getreader("utf-8")(fs).read()
 
         # read the spec from the build cache file. All specs in build caches
         # are concrete (as they are built) so we need to mark this spec
@@ -2734,8 +2706,9 @@ def get_keys(install=False, trust=False, force=False, mirrors=None):
 
         try:
             _, _, json_file = web_util.read_from_url(keys_index)
-            json_index = sjson.load(codecs.getreader("utf-8")(json_file))
-        except web_util.SpackWebError as url_err:
+            json_index = sjson.load(json_file)
+        except (web_util.SpackWebError, OSError, ValueError) as url_err:
+            # TODO: avoid repeated request
             if web_util.url_exists(keys_index):
                 tty.error(
                     f"Unable to find public keys in {url_util.format(fetch_url)},"
@@ -2982,14 +2955,14 @@ def __init__(self, url, local_hash, urlopen=web_util.urlopen):
 
     def get_remote_hash(self):
         # Failure to fetch index.json.hash is not fatal
-        url_index_hash = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, "index.json.hash")
+        url_index_hash = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, INDEX_HASH_FILE)
         try:
             response = self.urlopen(urllib.request.Request(url_index_hash, headers=self.headers))
-        except (TimeoutError, urllib.error.URLError):
+            remote_hash = response.read(64)
+        except OSError:
             return None
 
         # Validate the hash
-        remote_hash = response.read(64)
         if not re.match(rb"[a-f\d]{64}$", remote_hash):
             return None
         return remote_hash.decode("utf-8")
@@ -3003,17 +2976,17 @@ def conditional_fetch(self) -> FetchIndexResult:
             return FetchIndexResult(etag=None, hash=None, data=None, fresh=True)
 
         # Otherwise, download index.json
-        url_index = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, "index.json")
+        url_index = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, spack_db.INDEX_JSON_FILE)
 
         try:
             response = self.urlopen(urllib.request.Request(url_index, headers=self.headers))
-        except (TimeoutError, urllib.error.URLError) as e:
-            raise FetchIndexError("Could not fetch index from {}".format(url_index), e) from e
+        except OSError as e:
+            raise FetchIndexError(f"Could not fetch index from {url_index}", e) from e
 
         try:
             result = codecs.getreader("utf-8")(response).read()
-        except ValueError as e:
-            raise FetchIndexError("Remote index {} is invalid".format(url_index), e) from e
+        except (ValueError, OSError) as e:
+            raise FetchIndexError(f"Remote index {url_index} is invalid") from e
 
         computed_hash = compute_hash(result)
 
@@ -3047,7 +3020,7 @@ def __init__(self, url, etag, urlopen=web_util.urlopen):
 
     def conditional_fetch(self) -> FetchIndexResult:
         # Just do a conditional fetch immediately
-        url = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, "index.json")
+        url = url_util.join(self.url, BUILD_CACHE_RELATIVE_PATH, spack_db.INDEX_JSON_FILE)
         headers = {"User-Agent": web_util.SPACK_USER_AGENT, "If-None-Match": f'"{self.etag}"'}
 
         try:
@@ -3057,12 +3030,12 @@ def conditional_fetch(self) -> FetchIndexResult:
                 # Not modified; that means fresh.
                 return FetchIndexResult(etag=None, hash=None, data=None, fresh=True)
             raise FetchIndexError(f"Could not fetch index {url}", e) from e
-        except (TimeoutError, urllib.error.URLError) as e:
+        except OSError as e:  # URLError, socket.timeout, etc.
             raise FetchIndexError(f"Could not fetch index {url}", e) from e
 
         try:
             result = codecs.getreader("utf-8")(response).read()
-        except ValueError as e:
+        except (ValueError, OSError) as e:
             raise FetchIndexError(f"Remote index {url} is invalid", e) from e
 
         headers = response.headers
@@ -3094,11 +3067,11 @@ def conditional_fetch(self) -> FetchIndexResult:
                     headers={"Accept": "application/vnd.oci.image.manifest.v1+json"},
                 )
             )
-        except (TimeoutError, urllib.error.URLError) as e:
+        except OSError as e:
             raise FetchIndexError(f"Could not fetch manifest from {url_manifest}", e) from e
 
         try:
-            manifest = json.loads(response.read())
+            manifest = json.load(response)
         except Exception as e:
             raise FetchIndexError(f"Remote index {url_manifest} is invalid", e) from e
 
@@ -3113,14 +3086,16 @@ def conditional_fetch(self) -> FetchIndexResult:
             return FetchIndexResult(etag=None, hash=None, data=None, fresh=True)
 
         # Otherwise fetch the blob / index.json
-        response = self.urlopen(
-            urllib.request.Request(
-                url=self.ref.blob_url(index_digest),
-                headers={"Accept": "application/vnd.oci.image.layer.v1.tar+gzip"},
+        try:
+            response = self.urlopen(
+                urllib.request.Request(
+                    url=self.ref.blob_url(index_digest),
+                    headers={"Accept": "application/vnd.oci.image.layer.v1.tar+gzip"},
+                )
             )
-        )
-
-        result = codecs.getreader("utf-8")(response).read()
+            result = codecs.getreader("utf-8")(response).read()
+        except (OSError, ValueError) as e:
+            raise FetchIndexError(f"Remote index {url_manifest} is invalid", e) from e
 
         # Make sure the blob we download has the advertised hash
         if compute_hash(result) != index_digest.digest:

lib/spack/spack/bootstrap/_common.py

@@ -5,12 +5,14 @@
 import fnmatch
 import glob
 import importlib
-import os.path
+import os
 import re
 import sys
 import sysconfig
 import warnings
-from typing import Dict, Optional, Sequence, Union
+from typing import Optional, Sequence, Union
+
+from typing_extensions import TypedDict
 
 import archspec.cpu
 
@@ -18,13 +20,17 @@
 from llnl.util import tty
 
 import spack.platforms
+import spack.spec
 import spack.store
 import spack.util.environment
 import spack.util.executable
 
 from .config import spec_for_current_python
 
-QueryInfo = Dict[str, "spack.spec.Spec"]
+
+class QueryInfo(TypedDict, total=False):
+    spec: spack.spec.Spec
+    command: spack.util.executable.Executable
 
 
 def _python_import(module: str) -> bool:
@@ -211,7 +217,9 @@ def _executables_in_store(
             ):
                 spack.util.environment.path_put_first("PATH", [bin_dir])
                 if query_info is not None:
-                    query_info["command"] = spack.util.executable.which(*executables, path=bin_dir)
+                    query_info["command"] = spack.util.executable.which(
+                        *executables, path=bin_dir, required=True
+                    )
                     query_info["spec"] = concrete_spec
                 return True
     return False

lib/spack/spack/bootstrap/clingo.py

@@ -27,9 +27,9 @@
 class ClingoBootstrapConcretizer:
     def __init__(self, configuration):
         self.host_platform = spack.platforms.host()
-        self.host_os = self.host_platform.operating_system("frontend")
+        self.host_os = self.host_platform.default_operating_system()
         self.host_target = archspec.cpu.host().family
-        self.host_architecture = spack.spec.ArchSpec.frontend_arch()
+        self.host_architecture = spack.spec.ArchSpec.default_arch()
         self.host_architecture.target = str(self.host_target)
         self.host_compiler = self._valid_compiler_or_raise()
         self.host_python = self.python_external_spec()

lib/spack/spack/bootstrap/config.py

@@ -4,7 +4,7 @@
 """Manage configuration swapping for bootstrapping purposes"""
 
 import contextlib
-import os.path
+import os
 import sys
 from typing import Any, Dict, Generator, MutableSequence, Sequence
 
@@ -141,7 +141,7 @@ def _bootstrap_config_scopes() -> Sequence["spack.config.ConfigScope"]:
 
 
 def _add_compilers_if_missing() -> None:
-    arch = spack.spec.ArchSpec.frontend_arch()
+    arch = spack.spec.ArchSpec.default_arch()
     if not spack.compilers.compilers_for_arch(arch):
         spack.compilers.find_compilers()
 

lib/spack/spack/bootstrap/core.py

@@ -25,7 +25,6 @@
 import functools
 import json
 import os
-import os.path
 import sys
 import uuid
 from typing import Any, Callable, Dict, List, Optional, Tuple
@@ -34,8 +33,10 @@
 from llnl.util.lang import GroupedExceptionHandler
 
 import spack.binary_distribution
+import spack.concretize
 import spack.config
 import spack.detection
+import spack.error
 import spack.mirrors.mirror
 import spack.platforms
 import spack.spec
@@ -44,10 +45,17 @@
 import spack.util.executable
 import spack.util.path
 import spack.util.spack_yaml
+import spack.util.url
 import spack.version
 from spack.installer import PackageInstaller
 
-from ._common import _executables_in_store, _python_import, _root_spec, _try_import_from_store
+from ._common import (
+    QueryInfo,
+    _executables_in_store,
+    _python_import,
+    _root_spec,
+    _try_import_from_store,
+)
 from .clingo import ClingoBootstrapConcretizer
 from .config import spack_python_interpreter, spec_for_current_python
 
@@ -89,8 +97,12 @@ def __init__(self, conf: ConfigDictionary) -> None:
         self.name = conf["name"]
         self.metadata_dir = spack.util.path.canonicalize_path(conf["metadata"])
 
-        # Promote (relative) paths to file urls
-        self.url = spack.mirrors.mirror.Mirror(conf["info"]["url"]).fetch_url
+        # Check for relative paths, and turn them into absolute paths
+        # root is the metadata_dir
+        maybe_url = conf["info"]["url"]
+        if spack.util.url.is_path_instead_of_url(maybe_url) and not os.path.isabs(maybe_url):
+            maybe_url = os.path.join(self.metadata_dir, maybe_url)
+        self.url = spack.mirrors.mirror.Mirror(maybe_url).fetch_url
 
     @property
     def mirror_scope(self) -> spack.config.InternalConfigScope:
@@ -134,7 +146,7 @@ class BuildcacheBootstrapper(Bootstrapper):
 
     def __init__(self, conf) -> None:
         super().__init__(conf)
-        self.last_search: Optional[ConfigDictionary] = None
+        self.last_search: Optional[QueryInfo] = None
         self.config_scope_name = f"bootstrap_buildcache-{uuid.uuid4()}"
 
     @staticmethod
@@ -211,14 +223,14 @@ def _install_and_test(
                 for _, pkg_hash, pkg_sha256 in item["binaries"]:
                     self._install_by_hash(pkg_hash, pkg_sha256, bincache_platform)
 
-                info: ConfigDictionary = {}
+                info: QueryInfo = {}
                 if test_fn(query_spec=abstract_spec, query_info=info):
                     self.last_search = info
                     return True
         return False
 
     def try_import(self, module: str, abstract_spec_str: str) -> bool:
-        info: ConfigDictionary
+        info: QueryInfo
         test_fn, info = functools.partial(_try_import_from_store, module), {}
         if test_fn(query_spec=abstract_spec_str, query_info=info):
             return True
@@ -231,7 +243,7 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
         return self._install_and_test(abstract_spec, bincache_platform, data, test_fn)
 
     def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bool:
-        info: ConfigDictionary
+        info: QueryInfo
         test_fn, info = functools.partial(_executables_in_store, executables), {}
         if test_fn(query_spec=abstract_spec_str, query_info=info):
             self.last_search = info
@@ -249,11 +261,11 @@ class SourceBootstrapper(Bootstrapper):
 
     def __init__(self, conf) -> None:
         super().__init__(conf)
-        self.last_search: Optional[ConfigDictionary] = None
+        self.last_search: Optional[QueryInfo] = None
         self.config_scope_name = f"bootstrap_source-{uuid.uuid4()}"
 
     def try_import(self, module: str, abstract_spec_str: str) -> bool:
-        info: ConfigDictionary = {}
+        info: QueryInfo = {}
         if _try_import_from_store(module, abstract_spec_str, query_info=info):
             self.last_search = info
             return True
@@ -270,10 +282,10 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
                 bootstrapper = ClingoBootstrapConcretizer(configuration=spack.config.CONFIG)
                 concrete_spec = bootstrapper.concretize()
             else:
-                concrete_spec = spack.spec.Spec(
+                abstract_spec = spack.spec.Spec(
                     abstract_spec_str + " ^" + spec_for_current_python()
                 )
-                concrete_spec.concretize()
+                concrete_spec = spack.concretize.concretize_one(abstract_spec)
 
         msg = "[BOOTSTRAP MODULE {0}] Try installing '{1}' from sources"
         tty.debug(msg.format(module, abstract_spec_str))
@@ -288,7 +300,7 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
         return False
 
     def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bool:
-        info: ConfigDictionary = {}
+        info: QueryInfo = {}
         if _executables_in_store(executables, abstract_spec_str, query_info=info):
             self.last_search = info
             return True
@@ -299,7 +311,7 @@ def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bo
         # might reduce compilation time by a fair amount
         _add_externals_if_missing()
 
-        concrete_spec = spack.spec.Spec(abstract_spec_str).concretized()
+        concrete_spec = spack.concretize.concretize_one(abstract_spec_str)
         msg = "[BOOTSTRAP] Try installing '{0}' from sources"
         tty.debug(msg.format(abstract_spec_str))
         with spack.config.override(self.mirror_scope):
@@ -316,11 +328,9 @@ def create_bootstrapper(conf: ConfigDictionary):
     return _bootstrap_methods[btype](conf)
 
 
-def source_is_enabled_or_raise(conf: ConfigDictionary):
-    """Raise ValueError if the source is not enabled for bootstrapping"""
-    trusted, name = spack.config.get("bootstrap:trusted"), conf["name"]
-    if not trusted.get(name, False):
-        raise ValueError("source is not trusted")
+def source_is_enabled(conf: ConfigDictionary) -> bool:
+    """Returns true if the source is not enabled for bootstrapping"""
+    return spack.config.get("bootstrap:trusted").get(conf["name"], False)
 
 
 def ensure_module_importable_or_raise(module: str, abstract_spec: Optional[str] = None):
@@ -350,24 +360,23 @@ def ensure_module_importable_or_raise(module: str, abstract_spec: Optional[str]
     exception_handler = GroupedExceptionHandler()
 
     for current_config in bootstrapping_sources():
+        if not source_is_enabled(current_config):
+            continue
         with exception_handler.forward(current_config["name"], Exception):
-            source_is_enabled_or_raise(current_config)
-            current_bootstrapper = create_bootstrapper(current_config)
-            if current_bootstrapper.try_import(module, abstract_spec):
+            if create_bootstrapper(current_config).try_import(module, abstract_spec):
                 return
 
-    assert exception_handler, (
-        f"expected at least one exception to have been raised at this point: "
-        f"while bootstrapping {module}"
-    )
     msg = f'cannot bootstrap the "{module}" Python module '
     if abstract_spec:
         msg += f'from spec "{abstract_spec}" '
-    if tty.is_debug():
+
+    if not exception_handler:
+        msg += ": no bootstrapping sources are enabled"
+    elif spack.error.debug or spack.error.SHOW_BACKTRACE:
         msg += exception_handler.grouped_message(with_tracebacks=True)
     else:
         msg += exception_handler.grouped_message(with_tracebacks=False)
-        msg += "\nRun `spack --debug ...` for more detailed errors"
+        msg += "\nRun `spack --backtrace ...` for more detailed errors"
     raise ImportError(msg)
 
 
@@ -405,8 +414,9 @@ def ensure_executables_in_path_or_raise(
     exception_handler = GroupedExceptionHandler()
 
     for current_config in bootstrapping_sources():
+        if not source_is_enabled(current_config):
+            continue
         with exception_handler.forward(current_config["name"], Exception):
-            source_is_enabled_or_raise(current_config)
             current_bootstrapper = create_bootstrapper(current_config)
             if current_bootstrapper.try_search_path(executables, abstract_spec):
                 # Additional environment variables needed
@@ -414,6 +424,7 @@ def ensure_executables_in_path_or_raise(
                     current_bootstrapper.last_search["spec"],
                     current_bootstrapper.last_search["command"],
                 )
+                assert cmd is not None, "expected an Executable"
                 cmd.add_default_envmod(
                     spack.user_environment.environment_modifications_for_specs(
                         concrete_spec, set_package_py_globals=False
@@ -421,18 +432,17 @@ def ensure_executables_in_path_or_raise(
                 )
                 return cmd
 
-    assert exception_handler, (
-        f"expected at least one exception to have been raised at this point: "
-        f"while bootstrapping {executables_str}"
-    )
     msg = f"cannot bootstrap any of the {executables_str} executables "
     if abstract_spec:
         msg += f'from spec "{abstract_spec}" '
-    if tty.is_debug():
+
+    if not exception_handler:
+        msg += ": no bootstrapping sources are enabled"
+    elif spack.error.debug or spack.error.SHOW_BACKTRACE:
         msg += exception_handler.grouped_message(with_tracebacks=True)
     else:
         msg += exception_handler.grouped_message(with_tracebacks=False)
-        msg += "\nRun `spack --debug ...` for more detailed errors"
+        msg += "\nRun `spack --backtrace ...` for more detailed errors"
     raise RuntimeError(msg)
 
 

lib/spack/spack/bootstrap/status.py

@@ -63,7 +63,6 @@ def _missing(name: str, purpose: str, system_only: bool = True) -> str:
 
 def _core_requirements() -> List[RequiredResponseType]:
     _core_system_exes = {
-        "make": _missing("make", "required to build software from sources"),
         "patch": _missing("patch", "required to patch source code before building"),
         "tar": _missing("tar", "required to manage code archives"),
         "gzip": _missing("gzip", "required to compress/decompress code archives"),

lib/spack/spack/build_environment.py

@@ -44,7 +44,19 @@
 from enum import Flag, auto
 from itertools import chain
 from multiprocessing.connection import Connection
-from typing import Callable, Dict, List, Optional, Set, Tuple
+from typing import (
+    Callable,
+    Dict,
+    List,
+    Optional,
+    Sequence,
+    Set,
+    TextIO,
+    Tuple,
+    Type,
+    Union,
+    overload,
+)
 
 import archspec.cpu
 
@@ -146,48 +158,128 @@ def get_effective_jobs(jobs, parallel=True, supports_jobserver=False):
 
 
 class MakeExecutable(Executable):
-    """Special callable executable object for make so the user can specify
-    parallelism options on a per-invocation basis.  Specifying
-    'parallel' to the call will override whatever the package's
-    global setting is, so you can either default to true or false and
-    override particular calls. Specifying 'jobs_env' to a particular
-    call will name an environment variable which will be set to the
-    parallelism level (without affecting the normal invocation with
-    -j).
+    """Special callable executable object for make so the user can specify parallelism options
+    on a per-invocation basis.
     """
 
-    def __init__(self, name, jobs, **kwargs):
-        supports_jobserver = kwargs.pop("supports_jobserver", True)
-        super().__init__(name, **kwargs)
+    def __init__(self, name: str, *, jobs: int, supports_jobserver: bool = True) -> None:
+        super().__init__(name)
         self.supports_jobserver = supports_jobserver
         self.jobs = jobs
 
-    def __call__(self, *args, **kwargs):
-        """parallel, and jobs_env from kwargs are swallowed and used here;
-        remaining arguments are passed through to the superclass.
-        """
-        parallel = kwargs.pop("parallel", True)
-        jobs_env = kwargs.pop("jobs_env", None)
-        jobs_env_supports_jobserver = kwargs.pop("jobs_env_supports_jobserver", False)
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Optional[TextIO], str] = ...,
+        error: Union[Optional[TextIO], str] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> None: ...
 
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Type[str], Callable] = ...,
+        error: Union[Optional[TextIO], str, Type[str], Callable] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> str: ...
+
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Optional[TextIO], str, Type[str], Callable] = ...,
+        error: Union[Type[str], Callable] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> str: ...
+
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = True,
+        jobs_env: Optional[str] = None,
+        jobs_env_supports_jobserver: bool = False,
+        **kwargs,
+    ) -> Optional[str]:
+        """Runs this "make" executable in a subprocess.
+
+        Args:
+            parallel: if False, parallelism is disabled
+            jobs_env: environment variable that will be set to the current level of parallelism
+            jobs_env_supports_jobserver: whether the jobs env supports a job server
+
+        For all the other **kwargs, refer to the base class.
+        """
         jobs = get_effective_jobs(
             self.jobs, parallel=parallel, supports_jobserver=self.supports_jobserver
         )
         if jobs is not None:
-            args = ("-j{0}".format(jobs),) + args
+            args = (f"-j{jobs}",) + args
 
         if jobs_env:
-            # Caller wants us to set an environment variable to
-            # control the parallelism.
+            # Caller wants us to set an environment variable to control the parallelism
             jobs_env_jobs = get_effective_jobs(
                 self.jobs, parallel=parallel, supports_jobserver=jobs_env_supports_jobserver
             )
             if jobs_env_jobs is not None:
-                kwargs["extra_env"] = {jobs_env: str(jobs_env_jobs)}
+                extra_env = kwargs.setdefault("extra_env", {})
+                extra_env.update({jobs_env: str(jobs_env_jobs)})
 
         return super().__call__(*args, **kwargs)
 
 
+class UndeclaredDependencyError(spack.error.SpackError):
+    """Raised if a dependency is invoking an executable through a module global, without
+    declaring a dependency on it.
+    """
+
+
+class DeprecatedExecutable:
+    def __init__(self, pkg: str, exe: str, exe_pkg: str) -> None:
+        self.pkg = pkg
+        self.exe = exe
+        self.exe_pkg = exe_pkg
+
+    def __call__(self, *args, **kwargs):
+        raise UndeclaredDependencyError(
+            f"{self.pkg} is using {self.exe} without declaring a dependency on {self.exe_pkg}"
+        )
+
+    def add_default_env(self, key: str, value: str):
+        self.__call__()
+
+
 def clean_environment():
     # Stuff in here sanitizes the build environment to eliminate
     # anything the user has set that may interfere. We apply it immediately
@@ -209,11 +301,13 @@ def clean_environment():
     env.unset("CPLUS_INCLUDE_PATH")
     env.unset("OBJC_INCLUDE_PATH")
 
+    # prevent configure scripts from sourcing variables from config site file (AC_SITE_LOAD).
+    env.set("CONFIG_SITE", os.devnull)
     env.unset("CMAKE_PREFIX_PATH")
+
     env.unset("PYTHONPATH")
     env.unset("R_HOME")
     env.unset("R_ENVIRON")
-
     env.unset("LUA_PATH")
     env.unset("LUA_CPATH")
 
@@ -516,9 +610,11 @@ def set_wrapper_variables(pkg, env):
     if spack.config.get("config:ccache"):
         # Enable ccache in the compiler wrapper
         env.set(SPACK_CCACHE_BINARY, spack.util.executable.which_string("ccache", required=True))
+        env.set("CCACHE_NOHASHDIR", "")
+        env.set("CCACHE_BASEDIR", os.path.realpath(spack.stage.get_stage_root()))
     else:
         # Avoid cache pollution if a build system forces `ccache <compiler wrapper invocation>`.
-        env.set("CCACHE_DISABLE", "1")
+        env.set("CCACHE_DISABLE", "")
 
     # Gather information about various types of dependencies
     rpath_hashes = set(s.dag_hash() for s in get_rpath_deps(pkg))
@@ -621,10 +717,9 @@ def set_package_py_globals(pkg, context: Context = Context.BUILD):
         module.std_meson_args = spack.build_systems.meson.MesonBuilder.std_args(pkg)
         module.std_pip_args = spack.build_systems.python.PythonPipBuilder.std_args(pkg)
 
-    # TODO: make these build deps that can be installed if not found.
-    module.make = MakeExecutable("make", jobs)
-    module.gmake = MakeExecutable("gmake", jobs)
-    module.ninja = MakeExecutable("ninja", jobs, supports_jobserver=False)
+    module.make = DeprecatedExecutable(pkg.name, "make", "gmake")
+    module.gmake = DeprecatedExecutable(pkg.name, "gmake", "gmake")
+    module.ninja = DeprecatedExecutable(pkg.name, "ninja", "ninja")
     # TODO: johnwparent: add package or builder support to define these build tools
     # for now there is no entrypoint for builders to define these on their
     # own

lib/spack/spack/build_systems/aspell_dict.py

@@ -6,7 +6,9 @@
 import llnl.util.filesystem as fs
 
 import spack.directives
+import spack.spec
 import spack.util.executable
+import spack.util.prefix
 
 from .autotools import AutotoolsBuilder, AutotoolsPackage
 
@@ -17,19 +19,18 @@ class AspellBuilder(AutotoolsBuilder):
     to the Aspell extensions.
     """
 
-    def configure(self, pkg, spec, prefix):
+    def configure(
+        self,
+        pkg: "AspellDictPackage",  # type: ignore[override]
+        spec: spack.spec.Spec,
+        prefix: spack.util.prefix.Prefix,
+    ):
         aspell = spec["aspell"].prefix.bin.aspell
         prezip = spec["aspell"].prefix.bin.prezip
         destdir = prefix
 
-        sh = spack.util.executable.which("sh")
-        sh(
-            "./configure",
-            "--vars",
-            "ASPELL={0}".format(aspell),
-            "PREZIP={0}".format(prezip),
-            "DESTDIR={0}".format(destdir),
-        )
+        sh = spack.util.executable.Executable("/bin/sh")
+        sh("./configure", "--vars", f"ASPELL={aspell}", f"PREZIP={prezip}", f"DESTDIR={destdir}")
 
 
 # Aspell dictionaries install their bits into their prefix.lib

lib/spack/spack/build_systems/autotools.py

@@ -2,7 +2,6 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import os
-import os.path
 import stat
 import subprocess
 from typing import Callable, List, Optional, Set, Tuple, Union
@@ -356,6 +355,13 @@ def _do_patch_libtool_configure(self) -> None:
             )
             # Support Libtool 2.4.2 and older:
             x.filter(regex=r'^(\s*test \$p = "-R")(; then\s*)$', repl=r'\1 || test x-l = x"$p"\2')
+            # Configure scripts generated with libtool < 2.5.4 have a faulty test for the
+            # -single_module linker flag. A deprecation warning makes it think the default is
+            # -multi_module, triggering it to use problematic linker flags (such as ld -r). The
+            # linker default is `-single_module` from (ancient) macOS 10.4, so override by setting
+            # `lt_cv_apple_cc_single_mod=yes`. See the fix in libtool commit
+            # 82f7f52123e4e7e50721049f7fa6f9b870e09c9d.
+            x.filter("lt_cv_apple_cc_single_mod=no", "lt_cv_apple_cc_single_mod=yes", string=True)
 
     @spack.phase_callbacks.run_after("configure")
     def _do_patch_libtool(self) -> None:
@@ -527,7 +533,7 @@ def build_directory(self) -> str:
         return build_dir
 
     @spack.phase_callbacks.run_before("autoreconf")
-    def delete_configure_to_force_update(self) -> None:
+    def _delete_configure_to_force_update(self) -> None:
         if self.force_autoreconf:
             fs.force_remove(self.configure_abs_path)
 
@@ -540,7 +546,7 @@ def autoreconf_search_path_args(self) -> List[str]:
         return _autoreconf_search_path_args(self.spec)
 
     @spack.phase_callbacks.run_after("autoreconf")
-    def set_configure_or_die(self) -> None:
+    def _set_configure_or_die(self) -> None:
         """Ensure the presence of a "configure" script, or raise. If the "configure"
         is found, a module level attribute is set.
 
@@ -564,10 +570,7 @@ def configure_args(self) -> List[str]:
         return []
 
     def autoreconf(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: AutotoolsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Not needed usually, configure should be already there"""
 
@@ -596,10 +599,7 @@ def autoreconf(
             self.pkg.module.autoreconf(*autoreconf_args)
 
     def configure(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: AutotoolsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run "configure", with the arguments specified by the builder and an
         appropriately set prefix.
@@ -612,10 +612,7 @@ def configure(
             pkg.module.configure(*options)
 
     def build(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: AutotoolsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run "make" on the build targets specified by the builder."""
         # See https://autotools.io/automake/silent.html
@@ -625,10 +622,7 @@ def build(
             pkg.module.make(*params)
 
     def install(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: AutotoolsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run "make" on the install targets specified by the builder."""
         with fs.working_dir(self.build_directory):
@@ -825,7 +819,7 @@ def installcheck(self) -> None:
             self.pkg._if_make_target_execute("installcheck")
 
     @spack.phase_callbacks.run_after("install")
-    def remove_libtool_archives(self) -> None:
+    def _remove_libtool_archives(self) -> None:
         """Remove all .la files in prefix sub-folders if the package sets
         ``install_libtool_archives`` to be False.
         """

lib/spack/spack/build_systems/cached_cmake.py

@@ -10,6 +10,8 @@
 import llnl.util.tty as tty
 
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 
 from .cmake import CMakeBuilder, CMakePackage
 
@@ -293,6 +295,13 @@ def initconfig_hardware_entries(self):
                 entries.append(cmake_cache_string("AMDGPU_TARGETS", arch_str))
                 entries.append(cmake_cache_string("GPU_TARGETS", arch_str))
 
+            if spec.satisfies("%gcc"):
+                entries.append(
+                    cmake_cache_string(
+                        "CMAKE_HIP_FLAGS", f"--gcc-toolchain={self.pkg.compiler.prefix}"
+                    )
+                )
+
         return entries
 
     def std_initconfig_entries(self):
@@ -323,7 +332,9 @@ def initconfig_package_entries(self):
         """This method is to be overwritten by the package"""
         return []
 
-    def initconfig(self, pkg, spec, prefix):
+    def initconfig(
+        self, pkg: "CachedCMakePackage", spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         cache_entries = (
             self.std_initconfig_entries()
             + self.initconfig_compiler_entries()

lib/spack/spack/build_systems/cargo.py

@@ -7,6 +7,8 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on
 from spack.multimethod import when
 
@@ -81,12 +83,16 @@ def check_args(self):
     def setup_build_environment(self, env):
         env.set("CARGO_HOME", self.stage.path)
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: CargoPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Runs ``cargo install`` in the source directory"""
         with fs.working_dir(self.build_directory):
             pkg.module.cargo("install", "--root", "out", "--path", ".", *self.build_args)
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: CargoPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Copy build files into package prefix."""
         with fs.working_dir(self.build_directory):
             fs.install_tree("out", prefix)

lib/spack/spack/build_systems/cmake.py

@@ -454,18 +454,22 @@ def cmake_args(self) -> List[str]:
         return []
 
     def cmake(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: CMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Runs ``cmake`` in the build directory"""
 
-        # skip cmake phase if it is an incremental develop build
-        if spec.is_develop and os.path.isfile(
-            os.path.join(self.build_directory, "CMakeCache.txt")
-        ):
-            return
+        if spec.is_develop:
+            # skip cmake phase if it is an incremental develop build
+
+            # Determine the files that will re-run CMake that are generated from a successful
+            # configure step based on state
+            primary_generator = _extract_primary_generator(self.generator)
+            configure_artifact = "Makefile"
+            if primary_generator == "Ninja":
+                configure_artifact = "ninja.build"
+
+            if os.path.isfile(os.path.join(self.build_directory, configure_artifact)):
+                return
 
         options = self.std_cmake_args
         options += self.cmake_args()
@@ -474,10 +478,7 @@ def cmake(
             pkg.module.cmake(*options)
 
     def build(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: CMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Make the build targets"""
         with fs.working_dir(self.build_directory):
@@ -488,10 +489,7 @@ def build(
                 pkg.module.ninja(*self.build_targets)
 
     def install(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: CMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Make the install targets"""
         with fs.working_dir(self.build_directory):

lib/spack/spack/build_systems/cuda.py

@@ -15,7 +15,7 @@ class CudaPackage(PackageBase):
     """Auxiliary class which contains CUDA variant, dependencies and conflicts
     and is meant to unify and facilitate its usage.
 
-    Maintainers: ax3l, Rombur, davidbeckingsale
+    Maintainers: ax3l, Rombur, davidbeckingsale, pauleonix
     """
 
     # https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html#gpu-feature-list
@@ -47,6 +47,12 @@ class CudaPackage(PackageBase):
         "89",
         "90",
         "90a",
+        "100",
+        "100a",
+        "101",
+        "101a",
+        "120",
+        "120a",
     )
 
     # FIXME: keep cuda and cuda_arch separate to make usage easier until
@@ -99,39 +105,56 @@ def compute_capabilities(arch_list: Iterable[str]) -> List[str]:
     # CUDA version vs Architecture
     # https://en.wikipedia.org/wiki/CUDA#GPUs_supported
     # https://docs.nvidia.com/cuda/cuda-toolkit-release-notes/index.html#deprecated-features
+    # Tesla support:
     depends_on("cuda@:6.0", when="cuda_arch=10")
     depends_on("cuda@:6.5", when="cuda_arch=11")
     depends_on("cuda@2.1:6.5", when="cuda_arch=12")
     depends_on("cuda@2.1:6.5", when="cuda_arch=13")
 
+    # Fermi support:
     depends_on("cuda@3.0:8.0", when="cuda_arch=20")
     depends_on("cuda@3.2:8.0", when="cuda_arch=21")
 
+    # Kepler support:
     depends_on("cuda@5.0:10.2", when="cuda_arch=30")
     depends_on("cuda@5.0:10.2", when="cuda_arch=32")
     depends_on("cuda@5.0:11.8", when="cuda_arch=35")
     depends_on("cuda@6.5:11.8", when="cuda_arch=37")
 
+    # Maxwell support:
     depends_on("cuda@6.0:", when="cuda_arch=50")
     depends_on("cuda@6.5:", when="cuda_arch=52")
     depends_on("cuda@6.5:", when="cuda_arch=53")
 
+    # Pascal support:
     depends_on("cuda@8.0:", when="cuda_arch=60")
     depends_on("cuda@8.0:", when="cuda_arch=61")
     depends_on("cuda@8.0:", when="cuda_arch=62")
 
+    # Volta support:
     depends_on("cuda@9.0:", when="cuda_arch=70")
+    # Turing support:
     depends_on("cuda@9.0:", when="cuda_arch=72")
     depends_on("cuda@10.0:", when="cuda_arch=75")
 
+    # Ampere support:
     depends_on("cuda@11.0:", when="cuda_arch=80")
     depends_on("cuda@11.1:", when="cuda_arch=86")
     depends_on("cuda@11.4:", when="cuda_arch=87")
+    # Ada support:
     depends_on("cuda@11.8:", when="cuda_arch=89")
 
+    # Hopper support:
     depends_on("cuda@12.0:", when="cuda_arch=90")
     depends_on("cuda@12.0:", when="cuda_arch=90a")
 
+    # Blackwell support:
+    depends_on("cuda@12.8:", when="cuda_arch=100")
+    depends_on("cuda@12.8:", when="cuda_arch=100a")
+    depends_on("cuda@12.8:", when="cuda_arch=101")
+    depends_on("cuda@12.8:", when="cuda_arch=101a")
+    depends_on("cuda@12.8:", when="cuda_arch=120")
+    depends_on("cuda@12.8:", when="cuda_arch=120a")
     # From the NVIDIA install guide we know of conflicts for particular
     # platforms (linux, darwin), architectures (x86, powerpc) and compilers
     # (gcc, clang). We don't restrict %gcc and %clang conflicts to
@@ -163,6 +186,7 @@ def compute_capabilities(arch_list: Iterable[str]) -> List[str]:
         conflicts("%gcc@12:", when="+cuda ^cuda@:11.8")
         conflicts("%gcc@13:", when="+cuda ^cuda@:12.3")
         conflicts("%gcc@14:", when="+cuda ^cuda@:12.6")
+        conflicts("%gcc@15:", when="+cuda ^cuda@:12.8")
         conflicts("%clang@12:", when="+cuda ^cuda@:11.4.0")
         conflicts("%clang@13:", when="+cuda ^cuda@:11.5")
         conflicts("%clang@14:", when="+cuda ^cuda@:11.7")
@@ -171,6 +195,7 @@ def compute_capabilities(arch_list: Iterable[str]) -> List[str]:
         conflicts("%clang@17:", when="+cuda ^cuda@:12.3")
         conflicts("%clang@18:", when="+cuda ^cuda@:12.5")
         conflicts("%clang@19:", when="+cuda ^cuda@:12.6")
+        conflicts("%clang@20:", when="+cuda ^cuda@:12.8")
 
         # https://gist.github.com/ax3l/9489132#gistcomment-3860114
         conflicts("%gcc@10", when="+cuda ^cuda@:11.4.0")

lib/spack/spack/build_systems/generic.py

@@ -7,6 +7,8 @@
 import spack.directives
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 
 from ._checks import BuilderWithDefaults, apply_macos_rpath_fixups, execute_install_time_tests
 
@@ -48,3 +50,8 @@ class GenericBuilder(BuilderWithDefaults):
 
     # unconditionally perform any post-install phase tests
     spack.phase_callbacks.run_after("install")(execute_install_time_tests)
+
+    def install(
+        self, pkg: Package, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
+        raise NotImplementedError

lib/spack/spack/build_systems/go.py

@@ -7,7 +7,9 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
-from spack.directives import build_system, extends
+import spack.spec
+import spack.util.prefix
+from spack.directives import build_system, depends_on
 from spack.multimethod import when
 
 from ._checks import BuilderWithDefaults, execute_install_time_tests
@@ -26,9 +28,7 @@ class GoPackage(spack.package_base.PackageBase):
     build_system("go")
 
     with when("build_system=go"):
-        # TODO: this seems like it should be depends_on, see
-        # setup_dependent_build_environment in go for why I kept it like this
-        extends("go@1.14:", type="build")
+        depends_on("go", type="build")
 
 
 @spack.builder.builder("go")
@@ -71,6 +71,7 @@ class GoBuilder(BuilderWithDefaults):
     def setup_build_environment(self, env):
         env.set("GO111MODULE", "on")
         env.set("GOTOOLCHAIN", "local")
+        env.set("GOPATH", fs.join_path(self.pkg.stage.path, "go"))
 
     @property
     def build_directory(self):
@@ -81,19 +82,31 @@ def build_directory(self):
     def build_args(self):
         """Arguments for ``go build``."""
         # Pass ldflags -s = --strip-all and -w = --no-warnings by default
-        return ["-modcacherw", "-ldflags", "-s -w", "-o", f"{self.pkg.name}"]
+        return [
+            "-p",
+            str(self.pkg.module.make_jobs),
+            "-modcacherw",
+            "-ldflags",
+            "-s -w",
+            "-o",
+            f"{self.pkg.name}",
+        ]
 
     @property
     def check_args(self):
         """Argument for ``go test`` during check phase"""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: GoPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Runs ``go build`` in the source directory"""
         with fs.working_dir(self.build_directory):
             pkg.module.go("build", *self.build_args)
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: GoPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install built binaries into prefix bin."""
         with fs.working_dir(self.build_directory):
             fs.mkdirp(prefix.bin)

lib/spack/spack/build_systems/lua.py

@@ -7,7 +7,9 @@
 
 import spack.builder
 import spack.package_base
+import spack.spec
 import spack.util.executable
+import spack.util.prefix
 from spack.directives import build_system, depends_on, extends
 from spack.multimethod import when
 
@@ -55,7 +57,9 @@ class LuaBuilder(spack.builder.Builder):
     #: Names associated with package attributes in the old build-system format
     legacy_attributes = ()
 
-    def unpack(self, pkg, spec, prefix):
+    def unpack(
+        self, pkg: LuaPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         if os.path.splitext(pkg.stage.archive_file)[1] == ".rock":
             directory = pkg.luarocks("unpack", pkg.stage.archive_file, output=str)
             dirlines = directory.split("\n")
@@ -66,15 +70,16 @@ def unpack(self, pkg, spec, prefix):
     def _generate_tree_line(name, prefix):
         return """{{ name = "{name}", root = "{prefix}" }};""".format(name=name, prefix=prefix)
 
-    def generate_luarocks_config(self, pkg, spec, prefix):
+    def generate_luarocks_config(
+        self, pkg: LuaPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         spec = self.pkg.spec
         table_entries = []
         for d in spec.traverse(deptype=("build", "run")):
             if d.package.extends(self.pkg.extendee_spec):
                 table_entries.append(self._generate_tree_line(d.name, d.prefix))
 
-        path = self._luarocks_config_path()
-        with open(path, "w", encoding="utf-8") as config:
+        with open(self._luarocks_config_path(), "w", encoding="utf-8") as config:
             config.write(
                 """
                 deps_mode="all"
@@ -85,23 +90,26 @@ def generate_luarocks_config(self, pkg, spec, prefix):
                     "\n".join(table_entries)
                 )
             )
-        return path
 
-    def preprocess(self, pkg, spec, prefix):
+    def preprocess(
+        self, pkg: LuaPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Override this to preprocess source before building with luarocks"""
         pass
 
     def luarocks_args(self):
         return []
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: LuaPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         rock = "."
         specs = find(".", "*.rockspec", recursive=False)
         if specs:
             rock = specs[0]
         rocks_args = self.luarocks_args()
         rocks_args.append(rock)
-        self.pkg.luarocks("--tree=" + prefix, "make", *rocks_args)
+        pkg.luarocks("--tree=" + prefix, "make", *rocks_args)
 
     def _luarocks_config_path(self):
         return os.path.join(self.pkg.stage.source_path, "spack_luarocks.lua")

lib/spack/spack/build_systems/makefile.py

@@ -98,29 +98,20 @@ def build_directory(self) -> str:
         return self.pkg.stage.source_path
 
     def edit(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MakefilePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Edit the Makefile before calling make. The default is a no-op."""
         pass
 
     def build(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MakefilePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run "make" on the build targets specified by the builder."""
         with fs.working_dir(self.build_directory):
             pkg.module.make(*self.build_targets)
 
     def install(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MakefilePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run "make" on the install targets specified by the builder."""
         with fs.working_dir(self.build_directory):

lib/spack/spack/build_systems/maven.py

@@ -5,6 +5,8 @@
 
 import spack.builder
 import spack.package_base
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on
 from spack.multimethod import when
 from spack.util.executable import which
@@ -58,16 +60,20 @@ def build_args(self):
         """List of args to pass to build phase."""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: MavenPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Compile code and package into a JAR file."""
         with fs.working_dir(self.build_directory):
-            mvn = which("mvn")
+            mvn = which("mvn", required=True)
             if self.pkg.run_tests:
                 mvn("verify", *self.build_args())
             else:
                 mvn("package", "-DskipTests", *self.build_args())
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: MavenPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Copy to installation prefix."""
         with fs.working_dir(self.build_directory):
             fs.install_tree(".", prefix)

lib/spack/spack/build_systems/meson.py

@@ -188,10 +188,7 @@ def meson_args(self) -> List[str]:
         return []
 
     def meson(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MesonPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Run ``meson`` in the build directory"""
         options = []
@@ -204,10 +201,7 @@ def meson(
             pkg.module.meson(*options)
 
     def build(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MesonPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Make the build targets"""
         options = ["-v"]
@@ -216,10 +210,7 @@ def build(
             pkg.module.ninja(*options)
 
     def install(
-        self,
-        pkg: spack.package_base.PackageBase,
-        spec: spack.spec.Spec,
-        prefix: spack.util.prefix.Prefix,
+        self, pkg: MesonPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
     ) -> None:
         """Make the install targets"""
         with fs.working_dir(self.build_directory):

lib/spack/spack/build_systems/msbuild.py

@@ -7,6 +7,8 @@
 
 import spack.builder
 import spack.package_base
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, conflicts
 
 from ._checks import BuilderWithDefaults
@@ -99,7 +101,9 @@ def msbuild_install_args(self):
         as `msbuild_args` by default."""
         return self.msbuild_args()
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: MSBuildPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run "msbuild" on the build targets specified by the builder."""
         with fs.working_dir(self.build_directory):
             pkg.module.msbuild(
@@ -108,7 +112,9 @@ def build(self, pkg, spec, prefix):
                 self.define_targets(*self.build_targets),
             )
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: MSBuildPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run "msbuild" on the install targets specified by the builder.
         This is INSTALL by default"""
         with fs.working_dir(self.build_directory):

lib/spack/spack/build_systems/nmake.py

@@ -7,6 +7,8 @@
 
 import spack.builder
 import spack.package_base
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, conflicts
 
 from ._checks import BuilderWithDefaults
@@ -123,7 +125,9 @@ def nmake_install_args(self):
         Individual packages should override to specify NMake args to command line"""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: NMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run "nmake" on the build targets specified by the builder."""
         opts = self.std_nmake_args
         opts += self.nmake_args()
@@ -132,7 +136,9 @@ def build(self, pkg, spec, prefix):
         with fs.working_dir(self.build_directory):
             pkg.module.nmake(*opts, *self.build_targets, ignore_quotes=self.ignore_quotes)
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: NMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run "nmake" on the install targets specified by the builder.
         This is INSTALL by default"""
         opts = self.std_nmake_args

lib/spack/spack/build_systems/octave.py

@@ -3,6 +3,8 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import spack.builder
 import spack.package_base
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, extends
 from spack.multimethod import when
 
@@ -42,7 +44,9 @@ class OctaveBuilder(BuilderWithDefaults):
     #: Names associated with package attributes in the old build-system format
     legacy_attributes = ()
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: OctavePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install the package from the archive file"""
         pkg.module.octave(
             "--quiet",

lib/spack/spack/build_systems/perl.py

@@ -10,6 +10,8 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on, extends
 from spack.install_test import SkipTest, test_part
 from spack.multimethod import when
@@ -149,7 +151,9 @@ def configure_args(self):
         """
         return []
 
-    def configure(self, pkg, spec, prefix):
+    def configure(
+        self, pkg: PerlPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run Makefile.PL or Build.PL with arguments consisting of
         an appropriate installation base directory followed by the
         list returned by :py:meth:`~.PerlBuilder.configure_args`.
@@ -173,7 +177,9 @@ def fix_shebang(self):
             repl = "#!/usr/bin/env perl"
             filter_file(pattern, repl, "Build", backup=False)
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: PerlPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Builds a Perl package."""
         self.build_executable()
 
@@ -184,6 +190,8 @@ def check(self):
         """Runs built-in tests of a Perl package."""
         self.build_executable("test")
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: PerlPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Installs a Perl package."""
         self.build_executable("install")

lib/spack/spack/build_systems/python.py

@@ -28,6 +28,7 @@
 import spack.repo
 import spack.spec
 import spack.store
+import spack.util.prefix
 from spack.directives import build_system, depends_on, extends
 from spack.error import NoHeadersError, NoLibrariesError
 from spack.install_test import test_part
@@ -263,16 +264,17 @@ def update_external_dependencies(self, extendee_spec=None):
                     # Ensure architecture information is present
                     if not python.architecture:
                         host_platform = spack.platforms.host()
-                        host_os = host_platform.operating_system("default_os")
-                        host_target = host_platform.target("default_target")
+                        host_os = host_platform.default_operating_system()
+                        host_target = host_platform.default_target()
                         python.architecture = spack.spec.ArchSpec(
                             (str(host_platform), str(host_os), str(host_target))
                         )
                     else:
                         if not python.architecture.platform:
                             python.architecture.platform = spack.platforms.host()
+                        platform = spack.platforms.by_name(python.architecture.platform)
                         if not python.architecture.os:
-                            python.architecture.os = "default_os"
+                            python.architecture.os = platform.default_operating_system()
                         if not python.architecture.target:
                             python.architecture.target = archspec.cpu.host().family.name
 

lib/spack/spack/build_systems/qmake.py

@@ -6,6 +6,8 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on
 
 from ._checks import BuilderWithDefaults, execute_build_time_tests
@@ -27,6 +29,7 @@ class QMakePackage(spack.package_base.PackageBase):
     build_system("qmake")
 
     depends_on("qmake", type="build", when="build_system=qmake")
+    depends_on("gmake", type="build")
 
 
 @spack.builder.builder("qmake")
@@ -61,17 +64,23 @@ def qmake_args(self):
         """List of arguments passed to qmake."""
         return []
 
-    def qmake(self, pkg, spec, prefix):
+    def qmake(
+        self, pkg: QMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Run ``qmake`` to configure the project and generate a Makefile."""
         with working_dir(self.build_directory):
             pkg.module.qmake(*self.qmake_args())
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: QMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Make the build targets"""
         with working_dir(self.build_directory):
             pkg.module.make()
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: QMakePackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Make the install targets"""
         with working_dir(self.build_directory):
             pkg.module.make("install")

lib/spack/spack/build_systems/r.py

@@ -94,7 +94,7 @@ def list_url(cls):
         if cls.cran:
             return f"https://cloud.r-project.org/src/contrib/Archive/{cls.cran}/"
 
-    @property
-    def git(self):
-        if self.bioc:
-            return f"https://git.bioconductor.org/packages/{self.bioc}"
+    @lang.classproperty
+    def git(cls):
+        if cls.bioc:
+            return f"https://git.bioconductor.org/packages/{cls.bioc}"

lib/spack/spack/build_systems/racket.py

@@ -9,6 +9,8 @@
 import llnl.util.tty as tty
 
 import spack.builder
+import spack.spec
+import spack.util.prefix
 from spack.build_environment import SPACK_NO_PARALLEL_MAKE
 from spack.config import determine_number_of_jobs
 from spack.directives import build_system, extends, maintainers
@@ -74,18 +76,22 @@ def build_directory(self):
             ret = os.path.join(ret, self.subdirectory)
         return ret
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: RacketPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install everything from build directory."""
         raco = Executable("raco")
         with fs.working_dir(self.build_directory):
-            parallel = self.pkg.parallel and (not env_flag(SPACK_NO_PARALLEL_MAKE))
+            parallel = pkg.parallel and (not env_flag(SPACK_NO_PARALLEL_MAKE))
+            name = pkg.racket_name
+            assert name is not None, "Racket package name is not set"
             args = [
                 "pkg",
                 "install",
                 "-t",
                 "dir",
                 "-n",
-                self.pkg.racket_name,
+                name,
                 "--deps",
                 "fail",
                 "--ignore-implies",
@@ -101,8 +107,7 @@ def install(self, pkg, spec, prefix):
             except ProcessError:
                 args.insert(-2, "--skip-installed")
                 raco(*args)
-                msg = (
-                    "Racket package {0} was already installed, uninstalling via "
+                tty.warn(
+                    f"Racket package {name} was already installed, uninstalling via "
                     "Spack may make someone unhappy!"
                 )
-                tty.warn(msg.format(self.pkg.racket_name))

lib/spack/spack/build_systems/rocm.py

@@ -140,7 +140,7 @@ class ROCmPackage(PackageBase):
         when="+rocm",
     )
 
-    depends_on("llvm-amdgpu", when="+rocm")
+    depends_on("llvm-amdgpu", type="build", when="+rocm")
     depends_on("hsa-rocr-dev", when="+rocm")
     depends_on("hip +rocm", when="+rocm")
 

lib/spack/spack/build_systems/ruby.py

@@ -5,6 +5,8 @@
 
 import spack.builder
 import spack.package_base
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, extends, maintainers
 
 from ._checks import BuilderWithDefaults
@@ -42,7 +44,9 @@ class RubyBuilder(BuilderWithDefaults):
     #: Names associated with package attributes in the old build-system format
     legacy_attributes = ()
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: RubyPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Build a Ruby gem."""
 
         # ruby-rake provides both rake.gemspec and Rakefile, but only
@@ -58,7 +62,9 @@ def build(self, pkg, spec, prefix):
             # Some Ruby packages only ship `*.gem` files, so nothing to build
             pass
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: RubyPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install a Ruby gem.
 
         The ruby package sets ``GEM_HOME`` to tell gem where to install to."""

lib/spack/spack/build_systems/scons.py

@@ -4,6 +4,8 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on
 
 from ._checks import BuilderWithDefaults, execute_build_time_tests
@@ -59,7 +61,9 @@ def build_args(self, spec, prefix):
         """Arguments to pass to build."""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: SConsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Build the package."""
         pkg.module.scons(*self.build_args(spec, prefix))
 
@@ -67,7 +71,9 @@ def install_args(self, spec, prefix):
         """Arguments to pass to install."""
         return []
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: SConsPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install the package."""
         pkg.module.scons("install", *self.install_args(spec, prefix))
 

lib/spack/spack/build_systems/sip.py

@@ -11,6 +11,8 @@
 import spack.install_test
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on, extends
 from spack.multimethod import when
 from spack.util.executable import Executable
@@ -41,6 +43,7 @@ class SIPPackage(spack.package_base.PackageBase):
     with when("build_system=sip"):
         extends("python", type=("build", "link", "run"))
         depends_on("py-sip", type="build")
+        depends_on("gmake", type="build")
 
     @property
     def import_modules(self):
@@ -130,7 +133,9 @@ class SIPBuilder(BuilderWithDefaults):
 
     build_directory = "build"
 
-    def configure(self, pkg, spec, prefix):
+    def configure(
+        self, pkg: SIPPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Configure the package."""
 
         # https://www.riverbankcomputing.com/static/Docs/sip/command_line_tools.html
@@ -148,7 +153,9 @@ def configure_args(self):
         """Arguments to pass to configure."""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: SIPPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Build the package."""
         args = self.build_args()
 
@@ -159,7 +166,9 @@ def build_args(self):
         """Arguments to pass to build."""
         return []
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: SIPPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Install the package."""
         args = self.install_args()
 

lib/spack/spack/build_systems/waf.py

@@ -6,6 +6,8 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
+import spack.spec
+import spack.util.prefix
 from spack.directives import build_system, depends_on
 
 from ._checks import BuilderWithDefaults, execute_build_time_tests, execute_install_time_tests
@@ -97,7 +99,9 @@ def waf(self, *args, **kwargs):
         with working_dir(self.build_directory):
             self.python("waf", "-j{0}".format(jobs), *args, **kwargs)
 
-    def configure(self, pkg, spec, prefix):
+    def configure(
+        self, pkg: WafPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Configures the project."""
         args = ["--prefix={0}".format(self.pkg.prefix)]
         args += self.configure_args()
@@ -108,7 +112,9 @@ def configure_args(self):
         """Arguments to pass to configure."""
         return []
 
-    def build(self, pkg, spec, prefix):
+    def build(
+        self, pkg: WafPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Executes the build."""
         args = self.build_args()
 
@@ -118,7 +124,9 @@ def build_args(self):
         """Arguments to pass to build."""
         return []
 
-    def install(self, pkg, spec, prefix):
+    def install(
+        self, pkg: WafPackage, spec: spack.spec.Spec, prefix: spack.util.prefix.Prefix
+    ) -> None:
         """Installs the targets on the system."""
         args = self.install_args()
 

lib/spack/spack/ci/__init__.py

@@ -14,8 +14,7 @@
 import zipfile
 from collections import namedtuple
 from typing import Callable, Dict, List, Set
-from urllib.error import HTTPError, URLError
-from urllib.request import HTTPHandler, Request, build_opener
+from urllib.request import Request
 
 import llnl.util.filesystem as fs
 import llnl.util.tty as tty
@@ -63,6 +62,8 @@
 
 PushResult = namedtuple("PushResult", "success url")
 
+urlopen = web_util.urlopen  # alias for mocking in tests
+
 
 def get_change_revisions():
     """If this is a git repo get the revisions to use when checking
@@ -472,12 +473,9 @@ def generate_pipeline(env: ev.Environment, args) -> None:
     # Use all unpruned specs to populate the build group for this set
     cdash_config = cfg.get("cdash")
     if options.cdash_handler and options.cdash_handler.auth_token:
-        try:
-            options.cdash_handler.populate_buildgroup(
-                [options.cdash_handler.build_name(s) for s in pipeline_specs]
-            )
-        except (SpackError, HTTPError, URLError, TimeoutError) as err:
-            tty.warn(f"Problem populating buildgroup: {err}")
+        options.cdash_handler.populate_buildgroup(
+            [options.cdash_handler.build_name(s) for s in pipeline_specs]
+        )
     elif cdash_config:
         # warn only if there was actually a CDash configuration.
         tty.warn("Unable to populate buildgroup without CDash credentials")
@@ -631,29 +629,19 @@ def download_and_extract_artifacts(url, work_dir):
     if token:
         headers["PRIVATE-TOKEN"] = token
 
-    opener = build_opener(HTTPHandler)
-
-    request = Request(url, headers=headers)
-    request.get_method = lambda: "GET"
-
-    response = opener.open(request, timeout=SPACK_CDASH_TIMEOUT)
-    response_code = response.getcode()
-
-    if response_code != 200:
-        msg = f"Error response code ({response_code}) in reproduce_ci_job"
-        raise SpackError(msg)
-
+    request = Request(url, headers=headers, method="GET")
     artifacts_zip_path = os.path.join(work_dir, "artifacts.zip")
+    os.makedirs(work_dir, exist_ok=True)
 
-    if not os.path.exists(work_dir):
-        os.makedirs(work_dir)
+    try:
+        response = urlopen(request, timeout=SPACK_CDASH_TIMEOUT)
+        with open(artifacts_zip_path, "wb") as out_file:
+            shutil.copyfileobj(response, out_file)
+    except OSError as e:
+        raise SpackError(f"Error fetching artifacts: {e}")
 
-    with open(artifacts_zip_path, "wb") as out_file:
-        shutil.copyfileobj(response, out_file)
-
-    zip_file = zipfile.ZipFile(artifacts_zip_path)
-    zip_file.extractall(work_dir)
-    zip_file.close()
+    with zipfile.ZipFile(artifacts_zip_path) as zip_file:
+        zip_file.extractall(work_dir)
 
     os.remove(artifacts_zip_path)
 

lib/spack/spack/ci/common.py

@@ -1,23 +1,21 @@
 # Copyright Spack Project Developers. See COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-import codecs
 import copy
 import json
 import os
 import re
-import ssl
 import sys
 import time
 from collections import deque
 from enum import Enum
 from typing import Dict, Generator, List, Optional, Set, Tuple
 from urllib.parse import quote, urlencode, urlparse
-from urllib.request import HTTPHandler, HTTPSHandler, Request, build_opener
+from urllib.request import Request
 
 import llnl.util.filesystem as fs
 import llnl.util.tty as tty
-from llnl.util.lang import Singleton, memoized
+from llnl.util.lang import memoized
 
 import spack.binary_distribution as bindist
 import spack.config as cfg
@@ -35,32 +33,11 @@
 from spack.reporters.cdash import SPACK_CDASH_TIMEOUT
 from spack.reporters.cdash import build_stamp as cdash_build_stamp
 
-
-def _urlopen():
-    error_handler = web_util.SpackHTTPDefaultErrorHandler()
-
-    # One opener with HTTPS ssl enabled
-    with_ssl = build_opener(
-        HTTPHandler(), HTTPSHandler(context=web_util.ssl_create_default_context()), error_handler
-    )
-
-    # One opener with HTTPS ssl disabled
-    without_ssl = build_opener(
-        HTTPHandler(), HTTPSHandler(context=ssl._create_unverified_context()), error_handler
-    )
-
-    # And dynamically dispatch based on the config:verify_ssl.
-    def dispatch_open(fullurl, data=None, timeout=None, verify_ssl=True):
-        opener = with_ssl if verify_ssl else without_ssl
-        timeout = timeout or cfg.get("config:connect_timeout", 1)
-        return opener.open(fullurl, data, timeout)
-
-    return dispatch_open
-
-
 IS_WINDOWS = sys.platform == "win32"
 SPACK_RESERVED_TAGS = ["public", "protected", "notary"]
-_dyn_mapping_urlopener = Singleton(_urlopen)
+
+# this exists purely for testing purposes
+_urlopen = web_util.urlopen
 
 
 def copy_files_to_artifacts(src, artifacts_dir):
@@ -279,26 +256,25 @@ def copy_test_results(self, source, dest):
         reports = fs.join_path(source, "*_Test*.xml")
         copy_files_to_artifacts(reports, dest)
 
-    def create_buildgroup(self, opener, headers, url, group_name, group_type):
+    def create_buildgroup(self, headers, url, group_name, group_type):
         data = {"newbuildgroup": group_name, "project": self.project, "type": group_type}
 
         enc_data = json.dumps(data).encode("utf-8")
 
         request = Request(url, data=enc_data, headers=headers)
 
-        response = opener.open(request, timeout=SPACK_CDASH_TIMEOUT)
-        response_code = response.getcode()
-
-        if response_code not in [200, 201]:
-            msg = f"Creating buildgroup failed (response code = {response_code})"
-            tty.warn(msg)
+        try:
+            response_text = _urlopen(request, timeout=SPACK_CDASH_TIMEOUT).read()
+        except OSError as e:
+            tty.warn(f"Failed to create CDash buildgroup: {e}")
             return None
 
-        response_text = response.read()
-        response_json = json.loads(response_text)
-        build_group_id = response_json["id"]
-
-        return build_group_id
+        try:
+            response_json = json.loads(response_text)
+            return response_json["id"]
+        except (json.JSONDecodeError, KeyError) as e:
+            tty.warn(f"Failed to parse CDash response: {e}")
+            return None
 
     def populate_buildgroup(self, job_names):
         url = f"{self.url}/api/v1/buildgroup.php"
@@ -308,16 +284,11 @@ def populate_buildgroup(self, job_names):
             "Content-Type": "application/json",
         }
 
-        opener = build_opener(HTTPHandler)
-
-        parent_group_id = self.create_buildgroup(opener, headers, url, self.build_group, "Daily")
-        group_id = self.create_buildgroup(
-            opener, headers, url, f"Latest {self.build_group}", "Latest"
-        )
+        parent_group_id = self.create_buildgroup(headers, url, self.build_group, "Daily")
+        group_id = self.create_buildgroup(headers, url, f"Latest {self.build_group}", "Latest")
 
         if not parent_group_id or not group_id:
-            msg = f"Failed to create or retrieve buildgroups for {self.build_group}"
-            tty.warn(msg)
+            tty.warn(f"Failed to create or retrieve buildgroups for {self.build_group}")
             return
 
         data = {
@@ -329,15 +300,12 @@ def populate_buildgroup(self, job_names):
 
         enc_data = json.dumps(data).encode("utf-8")
 
-        request = Request(url, data=enc_data, headers=headers)
-        request.get_method = lambda: "PUT"
+        request = Request(url, data=enc_data, headers=headers, method="PUT")
 
-        response = opener.open(request, timeout=SPACK_CDASH_TIMEOUT)
-        response_code = response.getcode()
-
-        if response_code != 200:
-            msg = f"Error response code ({response_code}) in populate_buildgroup"
-            tty.warn(msg)
+        try:
+            _urlopen(request, timeout=SPACK_CDASH_TIMEOUT)
+        except OSError as e:
+            tty.warn(f"Failed to populate CDash buildgroup: {e}")
 
     def report_skipped(self, spec: spack.spec.Spec, report_dir: str, reason: Optional[str]):
         """Explicitly report skipping testing of a spec (e.g., it's CI
@@ -735,9 +703,6 @@ def _apply_section(dest, src):
                 for value in header.values():
                     value = os.path.expandvars(value)
 
-                verify_ssl = mapping.get("verify_ssl", spack.config.get("config:verify_ssl", True))
-                timeout = mapping.get("timeout", spack.config.get("config:connect_timeout", 1))
-
                 required = mapping.get("require", [])
                 allowed = mapping.get("allow", [])
                 ignored = mapping.get("ignore", [])
@@ -771,19 +736,15 @@ def job_query(job):
                         endpoint_url._replace(query=query).geturl(), headers=header, method="GET"
                     )
                     try:
-                        response = _dyn_mapping_urlopener(
-                            request, verify_ssl=verify_ssl, timeout=timeout
-                        )
+                        response = _urlopen(request)
+                        config = json.load(response)
                     except Exception as e:
                         # For now just ignore any errors from dynamic mapping and continue
                         # This is still experimental, and failures should not stop CI
                         # from running normally
-                        tty.warn(f"Failed to fetch dynamic mapping for query:\n\t{query}")
-                        tty.warn(f"{e}")
+                        tty.warn(f"Failed to fetch dynamic mapping for query:\n\t{query}: {e}")
                         continue
 
-                    config = json.load(codecs.getreader("utf-8")(response))
-
                     # Strip ignore keys
                     if ignored:
                         for key in ignored:

lib/spack/spack/cmd/__init__.py

@@ -202,7 +202,7 @@ def _concretize_spec_pairs(
     # Special case for concretizing a single spec
     if len(to_concretize) == 1:
         abstract, concrete = to_concretize[0]
-        return [concrete or abstract.concretized(tests=tests)]
+        return [concrete or spack.concretize.concretize_one(abstract, tests=tests)]
 
     # Special case if every spec is either concrete or has an abstract hash
     if all(
@@ -254,9 +254,9 @@ def matching_spec_from_env(spec):
     """
     env = ev.active_environment()
     if env:
-        return env.matching_spec(spec) or spec.concretized()
+        return env.matching_spec(spec) or spack.concretize.concretize_one(spec)
     else:
-        return spec.concretized()
+        return spack.concretize.concretize_one(spec)
 
 
 def matching_specs_from_env(specs):
@@ -297,7 +297,7 @@ def disambiguate_spec(
 
 def disambiguate_spec_from_hashes(
     spec: spack.spec.Spec,
-    hashes: List[str],
+    hashes: Optional[List[str]],
     local: bool = False,
     installed: Union[bool, InstallRecordStatus] = True,
     first: bool = False,

lib/spack/spack/cmd/arch.py

@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 import collections
+import warnings
 
 import archspec.cpu
 
@@ -51,10 +52,10 @@ def setup_parser(subparser):
         "-t", "--target", action="store_true", default=False, help="print only the target"
     )
     parts2.add_argument(
-        "-f", "--frontend", action="store_true", default=False, help="print frontend"
+        "-f", "--frontend", action="store_true", default=False, help="print frontend (DEPRECATED)"
     )
     parts2.add_argument(
-        "-b", "--backend", action="store_true", default=False, help="print backend"
+        "-b", "--backend", action="store_true", default=False, help="print backend (DEPRECATED)"
     )
 
 
@@ -98,15 +99,14 @@ def arch(parser, args):
         display_targets(archspec.cpu.TARGETS)
         return
 
-    os_args, target_args = "default_os", "default_target"
     if args.frontend:
-        os_args, target_args = "frontend", "frontend"
+        warnings.warn("the argument --frontend is deprecated, and will be removed in Spack v1.0")
     elif args.backend:
-        os_args, target_args = "backend", "backend"
+        warnings.warn("the argument --backend is deprecated, and will be removed in Spack v1.0")
 
     host_platform = spack.platforms.host()
-    host_os = host_platform.operating_system(os_args)
-    host_target = host_platform.target(target_args)
+    host_os = host_platform.default_operating_system()
+    host_target = host_platform.default_target()
     if args.family:
         host_target = host_target.family
     elif args.generic:

lib/spack/spack/cmd/bootstrap.py

@@ -1,7 +1,7 @@
 # Copyright Spack Project Developers. See COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-import os.path
+import os
 import shutil
 import sys
 import tempfile
@@ -14,9 +14,9 @@
 import spack.bootstrap
 import spack.bootstrap.config
 import spack.bootstrap.core
+import spack.concretize
 import spack.config
 import spack.mirrors.utils
-import spack.spec
 import spack.stage
 import spack.util.path
 import spack.util.spack_yaml
@@ -397,7 +397,7 @@ def _mirror(args):
         llnl.util.tty.msg(msg.format(spec_str, mirror_dir))
         # Suppress tty from the call below for terser messages
         llnl.util.tty.set_msg_enabled(False)
-        spec = spack.spec.Spec(spec_str).concretized()
+        spec = spack.concretize.concretize_one(spec_str)
         for node in spec.traverse():
             spack.mirrors.utils.create(mirror_dir, [node])
         llnl.util.tty.set_msg_enabled(True)
@@ -436,6 +436,7 @@ def write_metadata(subdir, metadata):
         shutil.copy(spack.util.path.canonicalize_path(GNUPG_JSON), abs_directory)
         shutil.copy(spack.util.path.canonicalize_path(PATCHELF_JSON), abs_directory)
         instructions += cmd.format("local-binaries", rel_directory)
+        instructions += "  % spack buildcache update-index <final-path>/bootstrap_cache\n"
     print(instructions)
 
 

lib/spack/spack/cmd/buildcache.py

@@ -16,6 +16,7 @@
 
 import spack.binary_distribution as bindist
 import spack.cmd
+import spack.concretize
 import spack.config
 import spack.deptypes as dt
 import spack.environment as ev
@@ -554,8 +555,7 @@ def check_fn(args: argparse.Namespace):
         tty.msg("No specs provided, exiting.")
         return
 
-    for spec in specs:
-        spec.concretize()
+    specs = [spack.concretize.concretize_one(s) for s in specs]
 
     # Next see if there are any configured binary mirrors
     configured_mirrors = spack.config.get("mirrors", scope=args.scope)
@@ -623,7 +623,7 @@ def save_specfile_fn(args):
     root = specs[0]
 
     if not root.concrete:
-        root.concretize()
+        root = spack.concretize.concretize_one(root)
 
     save_dependency_specfiles(
         root, args.specfile_dir, dependencies=spack.cmd.parse_specs(args.specs)

lib/spack/spack/cmd/common/arguments.py

@@ -4,7 +4,7 @@
 
 
 import argparse
-import os.path
+import os
 import textwrap
 
 from llnl.util.lang import stable_partition

lib/spack/spack/cmd/containerize.py

@@ -2,7 +2,6 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import os
-import os.path
 
 import llnl.util.tty
 

lib/spack/spack/cmd/debug.py

@@ -86,8 +86,8 @@ def create_db_tarball(args):
 
 def report(args):
     host_platform = spack.platforms.host()
-    host_os = host_platform.operating_system("frontend")
-    host_target = host_platform.target("frontend")
+    host_os = host_platform.default_operating_system()
+    host_target = host_platform.default_target()
     architecture = spack.spec.ArchSpec((str(host_platform), str(host_os), str(host_target)))
     print("* **Spack:**", spack.get_version())
     print("* **Python:**", platform.python_version())

lib/spack/spack/cmd/deprecate.py

@@ -18,6 +18,7 @@
 from llnl.util.symlink import symlink
 
 import spack.cmd
+import spack.concretize
 import spack.environment as ev
 import spack.installer
 import spack.store
@@ -103,7 +104,7 @@ def deprecate(parser, args):
     )
 
     if args.install:
-        deprecator = specs[1].concretized()
+        deprecator = spack.concretize.concretize_one(specs[1])
     else:
         deprecator = spack.cmd.disambiguate_spec(specs[1], env, local=True)
 

lib/spack/spack/cmd/dev_build.py

@@ -10,6 +10,7 @@
 import spack.build_environment
 import spack.cmd
 import spack.cmd.common.arguments
+import spack.concretize
 import spack.config
 import spack.repo
 from spack.cmd.common import arguments
@@ -113,8 +114,8 @@ def dev_build(self, args):
     source_path = os.path.abspath(source_path)
 
     # Forces the build to run out of the source directory.
-    spec.constrain("dev_path=%s" % source_path)
-    spec.concretize()
+    spec.constrain(f'dev_path="{source_path}"')
+    spec = spack.concretize.concretize_one(spec)
 
     if spec.installed:
         tty.error("Already installed in %s" % spec.prefix)

lib/spack/spack/cmd/external.py

@@ -110,10 +110,7 @@ def external_find(args):
             # Note that KeyboardInterrupt does not subclass Exception
             # (so CTRL-C will terminate the program as expected).
             skip_msg = "Skipping manifest and continuing with other external checks"
-            if (isinstance(e, IOError) or isinstance(e, OSError)) and e.errno in [
-                errno.EPERM,
-                errno.EACCES,
-            ]:
+            if isinstance(e, OSError) and e.errno in (errno.EPERM, errno.EACCES):
                 # The manifest file does not have sufficient permissions enabled:
                 # print a warning and keep going
                 tty.warn("Unable to read manifest due to insufficient permissions.", skip_msg)

lib/spack/spack/cmd/help.py

@@ -54,10 +54,6 @@
       @m{target=target}                 specific <target> processor
       @m{arch=platform-os-target}       shortcut for all three above
 
-    cross-compiling:
-      @m{os=backend} or @m{os=be}           build for compute node (backend)
-      @m{os=frontend} or @m{os=fe}          build for login node (frontend)
-
     dependencies:
       ^dependency [constraints]     specify constraints on dependencies
       ^@K{/hash}                        build with a specific installed

lib/spack/spack/cmd/install.py

@@ -13,6 +13,7 @@
 from llnl.util import lang, tty
 
 import spack.cmd
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.paths
@@ -450,7 +451,7 @@ def concrete_specs_from_file(args):
             else:
                 s = spack.spec.Spec.from_json(f)
 
-        concretized = s.concretized()
+        concretized = spack.concretize.concretize_one(s)
         if concretized.dag_hash() != s.dag_hash():
             msg = 'skipped invalid file "{0}". '
             msg += "The file does not contain a concrete spec."

lib/spack/spack/cmd/make_installer.py

@@ -7,9 +7,9 @@
 
 from llnl.path import convert_to_posix_path
 
+import spack.concretize
 import spack.paths
 import spack.util.executable
-from spack.spec import Spec
 
 description = "generate Windows installer"
 section = "admin"
@@ -65,8 +65,7 @@ def make_installer(parser, args):
     """
     if sys.platform == "win32":
         output_dir = args.output_dir
-        cmake_spec = Spec("cmake")
-        cmake_spec.concretize()
+        cmake_spec = spack.concretize.concretize_one("cmake")
         cmake_path = os.path.join(cmake_spec.prefix, "bin", "cmake.exe")
         cpack_path = os.path.join(cmake_spec.prefix, "bin", "cpack.exe")
         spack_source = args.spack_source

lib/spack/spack/cmd/mirror.py

@@ -492,7 +492,7 @@ def extend_with_additional_versions(specs, num_versions):
         mirror_specs = spack.mirrors.utils.get_all_versions(specs)
     else:
         mirror_specs = spack.mirrors.utils.get_matching_versions(specs, num_versions=num_versions)
-    mirror_specs = [x.concretized() for x in mirror_specs]
+    mirror_specs = [spack.concretize.concretize_one(x) for x in mirror_specs]
     return mirror_specs
 
 

lib/spack/spack/cmd/modules/__init__.py

@@ -5,7 +5,7 @@
 """Implementation details of the ``spack module`` command."""
 
 import collections
-import os.path
+import os
 import shutil
 import sys
 

lib/spack/spack/cmd/test.py

@@ -177,16 +177,15 @@ def test_run(args):
         matching = spack.store.STORE.db.query_local(spec, hashes=hashes, explicit=explicit)
         if spec and not matching:
             tty.warn("No {0}installed packages match spec {1}".format(explicit_str, spec))
-            """
-            TODO: Need to write out a log message and/or CDASH Testing
-              output that package not installed IF continue to process
-              these issues here.
 
-            if args.log_format:
-                # Proceed with the spec assuming the test process
-                # to ensure report package as skipped (e.g., for CI)
-                specs_to_test.append(spec)
-            """
+            # TODO: Need to write out a log message and/or CDASH Testing
+            #   output that package not installed IF continue to process
+            #   these issues here.
+
+            # if args.log_format:
+            #     # Proceed with the spec assuming the test process
+            #     # to ensure report package as skipped (e.g., for CI)
+            #     specs_to_test.append(spec)
 
         specs_to_test.extend(matching)
 

lib/spack/spack/cmd/tutorial.py

@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-import os.path
+import os
 import shutil
 
 import llnl.util.tty as tty

lib/spack/spack/cmd/unit_test.py

@@ -5,7 +5,7 @@
 import argparse
 import collections
 import io
-import os.path
+import os
 import re
 import sys
 

lib/spack/spack/compilers/__init__.py

@@ -801,17 +801,17 @@ def _extract_compiler_paths(spec: "spack.spec.Spec") -> Optional[Dict[str, str]]
     def _extract_os_and_target(spec: "spack.spec.Spec"):
         if not spec.architecture:
             host_platform = spack.platforms.host()
-            operating_system = host_platform.operating_system("default_os")
-            target = host_platform.target("default_target")
+            operating_system = host_platform.default_operating_system()
+            target = host_platform.default_target()
         else:
             target = spec.architecture.target
             if not target:
-                target = spack.platforms.host().target("default_target")
+                target = spack.platforms.host().default_target()
 
             operating_system = spec.os
             if not operating_system:
                 host_platform = spack.platforms.host()
-                operating_system = host_platform.operating_system("default_os")
+                operating_system = host_platform.default_operating_system()
         return operating_system, target
 
 

lib/spack/spack/concretize.py

@@ -37,13 +37,12 @@ def enable_compiler_existence_check():
 
 SpecPairInput = Tuple[Spec, Optional[Spec]]
 SpecPair = Tuple[Spec, Spec]
-SpecLike = Union[Spec, str]
 TestsType = Union[bool, Iterable[str]]
 
 
-def concretize_specs_together(
-    abstract_specs: Sequence[SpecLike], tests: TestsType = False
-) -> Sequence[Spec]:
+def _concretize_specs_together(
+    abstract_specs: Sequence[Spec], tests: TestsType = False
+) -> List[Spec]:
     """Given a number of specs as input, tries to concretize them together.
 
     Args:
@@ -51,11 +50,10 @@ def concretize_specs_together(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.solver.asp
+    from spack.solver.asp import Solver
 
     allow_deprecated = spack.config.get("config:deprecated", False)
-    solver = spack.solver.asp.Solver()
-    result = solver.solve(abstract_specs, tests=tests, allow_deprecated=allow_deprecated)
+    result = Solver().solve(abstract_specs, tests=tests, allow_deprecated=allow_deprecated)
     return [s.copy() for s in result.specs]
 
 
@@ -72,7 +70,7 @@ def concretize_together(
     """
     to_concretize = [concrete if concrete else abstract for abstract, concrete in spec_list]
     abstract_specs = [abstract for abstract, _ in spec_list]
-    concrete_specs = concretize_specs_together(to_concretize, tests=tests)
+    concrete_specs = _concretize_specs_together(to_concretize, tests=tests)
     return list(zip(abstract_specs, concrete_specs))
 
 
@@ -90,7 +88,7 @@ def concretize_together_when_possible(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.solver.asp
+    from spack.solver.asp import Solver
 
     to_concretize = [concrete if concrete else abstract for abstract, concrete in spec_list]
     old_concrete_to_abstract = {
@@ -98,9 +96,8 @@ def concretize_together_when_possible(
     }
 
     result_by_user_spec = {}
-    solver = spack.solver.asp.Solver()
     allow_deprecated = spack.config.get("config:deprecated", False)
-    for result in solver.solve_in_rounds(
+    for result in Solver().solve_in_rounds(
         to_concretize, tests=tests, allow_deprecated=allow_deprecated
     ):
         result_by_user_spec.update(result.specs_by_input)
@@ -124,7 +121,7 @@ def concretize_separately(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.bootstrap
+    from spack.bootstrap import ensure_bootstrap_configuration, ensure_clingo_importable_or_raise
 
     to_concretize = [abstract for abstract, concrete in spec_list if not concrete]
     args = [
@@ -134,8 +131,8 @@ def concretize_separately(
     ]
     ret = [(i, abstract) for i, abstract in enumerate(to_concretize) if abstract.concrete]
     # Ensure we don't try to bootstrap clingo in parallel
-    with spack.bootstrap.ensure_bootstrap_configuration():
-        spack.bootstrap.ensure_clingo_importable_or_raise()
+    with ensure_bootstrap_configuration():
+        ensure_clingo_importable_or_raise()
 
     # Ensure all the indexes have been built or updated, since
     # otherwise the processes in the pool may timeout on waiting
@@ -190,10 +187,52 @@ def _concretize_task(packed_arguments: Tuple[int, str, TestsType]) -> Tuple[int,
     index, spec_str, tests = packed_arguments
     with tty.SuppressOutput(msg_enabled=False):
         start = time.time()
-        spec = Spec(spec_str).concretized(tests=tests)
+        spec = concretize_one(Spec(spec_str), tests=tests)
         return index, spec, time.time() - start
 
 
+def concretize_one(spec: Union[str, Spec], tests: TestsType = False) -> Spec:
+    """Return a concretized copy of the given spec.
+
+    Args:
+        tests: if False disregard 'test' dependencies, if a list of names activate them for
+            the packages in the list, if True activate 'test' dependencies for all packages.
+    """
+    from spack.solver.asp import Solver, SpecBuilder
+
+    if isinstance(spec, str):
+        spec = Spec(spec)
+    spec = spec.lookup_hash()
+
+    if spec.concrete:
+        return spec.copy()
+
+    for node in spec.traverse():
+        if not node.name:
+            raise spack.error.SpecError(
+                f"Spec {node} has no name; cannot concretize an anonymous spec"
+            )
+
+    allow_deprecated = spack.config.get("config:deprecated", False)
+    result = Solver().solve([spec], tests=tests, allow_deprecated=allow_deprecated)
+
+    # take the best answer
+    opt, i, answer = min(result.answers)
+    name = spec.name
+    # TODO: Consolidate this code with similar code in solve.py
+    if spec.virtual:
+        providers = [s.name for s in answer.values() if s.package.provides(name)]
+        name = providers[0]
+
+    node = SpecBuilder.make_node(pkg=name)
+    assert (
+        node in answer
+    ), f"cannot find {name} in the list of specs {','.join([n.pkg for n in answer.keys()])}"
+
+    concretized = answer[node]
+    return concretized
+
+
 class UnavailableCompilerVersionError(spack.error.SpackError):
     """Raised when there is no available compiler that satisfies a
     compiler spec."""

lib/spack/spack/config.py

@@ -36,6 +36,8 @@
 import sys
 from typing import Any, Callable, Dict, Generator, List, Optional, Tuple, Union
 
+import jsonschema
+
 from llnl.util import filesystem, lang, tty
 
 import spack.error
@@ -51,6 +53,7 @@
 import spack.schema.definitions
 import spack.schema.develop
 import spack.schema.env
+import spack.schema.env_vars
 import spack.schema.mirrors
 import spack.schema.modules
 import spack.schema.packages
@@ -68,6 +71,7 @@
     "compilers": spack.schema.compilers.schema,
     "concretizer": spack.schema.concretizer.schema,
     "definitions": spack.schema.definitions.schema,
+    "env_vars": spack.schema.env_vars.schema,
     "view": spack.schema.view.schema,
     "develop": spack.schema.develop.schema,
     "mirrors": spack.schema.mirrors.schema,
@@ -1048,8 +1052,6 @@ def validate(
     This leverages the line information (start_mark, end_mark) stored
     on Spack YAML structures.
     """
-    import jsonschema
-
     try:
         spack.schema.Validator(schema).validate(data)
     except jsonschema.ValidationError as e:

lib/spack/spack/container/__init__.py

@@ -6,6 +6,8 @@
 """
 import warnings
 
+import jsonschema
+
 import spack.environment as ev
 import spack.schema.env as env
 import spack.util.spack_yaml as syaml
@@ -30,8 +32,6 @@ def validate(configuration_file):
     Returns:
         A sanitized copy of the configuration stored in the input file
     """
-    import jsonschema
-
     with open(configuration_file, encoding="utf-8") as f:
         config = syaml.load(f)
 
@@ -57,7 +57,7 @@ def validate(configuration_file):
     # Set the default value of the concretization strategy to unify and
     # warn if the user explicitly set another value
     env_dict.setdefault("concretizer", {"unify": True})
-    if not env_dict["concretizer"]["unify"] is True:
+    if env_dict["concretizer"]["unify"] is not True:
         warnings.warn(
             '"concretizer:unify" is not set to "true", which means the '
             "generated image may contain different variants of the same "

lib/spack/spack/container/images.py

@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 """Manages the details on the images used in the various stages."""
 import json
-import os.path
+import os
 import shlex
 import sys
 

lib/spack/spack/container/writers.py

@@ -9,6 +9,8 @@
 from collections import namedtuple
 from typing import Optional
 
+import jsonschema
+
 import spack.environment as ev
 import spack.error
 import spack.schema.env
@@ -188,8 +190,6 @@ def paths(self):
     @tengine.context_property
     def manifest(self):
         """The spack.yaml file that should be used in the image"""
-        import jsonschema
-
         # Copy in the part of spack.yaml prescribed in the configuration file
         manifest = copy.deepcopy(self.config)
         manifest.pop("container")

lib/spack/spack/database.py

@@ -123,6 +123,15 @@
     "deprecated_for",
 )
 
+#: File where the database is written
+INDEX_JSON_FILE = "index.json"
+
+# Verifier file to check last modification of the DB
+_INDEX_VERIFIER_FILE = "index_verifier"
+
+# Lockfile for the database
+_LOCK_FILE = "lock"
+
 
 @llnl.util.lang.memoized
 def _getfqdn():
@@ -260,7 +269,7 @@ class ForbiddenLockError(SpackError):
 
 class ForbiddenLock:
     def __getattr__(self, name):
-        raise ForbiddenLockError("Cannot access attribute '{0}' of lock".format(name))
+        raise ForbiddenLockError(f"Cannot access attribute '{name}' of lock")
 
     def __reduce__(self):
         return ForbiddenLock, tuple()
@@ -419,14 +428,25 @@ class FailureTracker:
     the likelihood of collision very low with no cleanup required.
     """
 
+    #: root directory of the failure tracker
+    dir: pathlib.Path
+
+    #: File for locking particular concrete spec hashes
+    locker: SpecLocker
+
     def __init__(self, root_dir: Union[str, pathlib.Path], default_timeout: Optional[float]):
         #: Ensure a persistent location for dealing with parallel installation
         #: failures (e.g., across near-concurrent processes).
         self.dir = pathlib.Path(root_dir) / _DB_DIRNAME / "failures"
-        self.dir.mkdir(parents=True, exist_ok=True)
-
         self.locker = SpecLocker(failures_lock_path(root_dir), default_timeout=default_timeout)
 
+    def _ensure_parent_directories(self) -> None:
+        """Ensure that parent directories of the FailureTracker exist.
+
+        Accesses the filesystem only once, the first time it's called on a given FailureTracker.
+        """
+        self.dir.mkdir(parents=True, exist_ok=True)
+
     def clear(self, spec: "spack.spec.Spec", force: bool = False) -> None:
         """Removes any persistent and cached failure tracking for the spec.
 
@@ -469,13 +489,18 @@ def clear_all(self) -> None:
 
         tty.debug("Removing prefix failure tracking files")
         try:
-            for fail_mark in os.listdir(str(self.dir)):
-                try:
-                    (self.dir / fail_mark).unlink()
-                except OSError as exc:
-                    tty.warn(f"Unable to remove failure marking file {fail_mark}: {str(exc)}")
+            marks = os.listdir(str(self.dir))
+        except FileNotFoundError:
+            return  # directory doesn't exist yet
         except OSError as exc:
             tty.warn(f"Unable to remove failure marking files: {str(exc)}")
+            return
+
+        for fail_mark in marks:
+            try:
+                (self.dir / fail_mark).unlink()
+            except OSError as exc:
+                tty.warn(f"Unable to remove failure marking file {fail_mark}: {str(exc)}")
 
     def mark(self, spec: "spack.spec.Spec") -> lk.Lock:
         """Marks a spec as failing to install.
@@ -483,6 +508,8 @@ def mark(self, spec: "spack.spec.Spec") -> lk.Lock:
         Args:
             spec: spec that failed to install
         """
+        self._ensure_parent_directories()
+
         # Dump the spec to the failure file for (manual) debugging purposes
         path = self._path(spec)
         path.write_text(spec.to_json())
@@ -567,17 +594,13 @@ def __init__(
                 Relevant only if the repository is not an upstream.
         """
         self.root = root
-        self.database_directory = os.path.join(self.root, _DB_DIRNAME)
+        self.database_directory = pathlib.Path(self.root) / _DB_DIRNAME
         self.layout = layout
 
         # Set up layout of database files within the db dir
-        self._index_path = os.path.join(self.database_directory, "index.json")
-        self._verifier_path = os.path.join(self.database_directory, "index_verifier")
-        self._lock_path = os.path.join(self.database_directory, "lock")
-
-        # Create needed directories and files
-        if not is_upstream and not os.path.exists(self.database_directory):
-            fs.mkdirp(self.database_directory)
+        self._index_path = self.database_directory / INDEX_JSON_FILE
+        self._verifier_path = self.database_directory / _INDEX_VERIFIER_FILE
+        self._lock_path = self.database_directory / _LOCK_FILE
 
         self.is_upstream = is_upstream
         self.last_seen_verifier = ""
@@ -592,14 +615,14 @@ def __init__(
 
         # initialize rest of state.
         self.db_lock_timeout = lock_cfg.database_timeout
-        tty.debug("DATABASE LOCK TIMEOUT: {0}s".format(str(self.db_lock_timeout)))
+        tty.debug(f"DATABASE LOCK TIMEOUT: {str(self.db_lock_timeout)}s")
 
         self.lock: Union[ForbiddenLock, lk.Lock]
         if self.is_upstream:
             self.lock = ForbiddenLock()
         else:
             self.lock = lk.Lock(
-                self._lock_path,
+                str(self._lock_path),
                 default_timeout=self.db_lock_timeout,
                 desc="database",
                 enable=lock_cfg.enable,
@@ -616,6 +639,11 @@ def __init__(
         self._write_transaction_impl = lk.WriteTransaction
         self._read_transaction_impl = lk.ReadTransaction
 
+    def _ensure_parent_directories(self):
+        """Create the parent directory for the DB, if necessary."""
+        if not self.is_upstream:
+            self.database_directory.mkdir(parents=True, exist_ok=True)
+
     def write_transaction(self):
         """Get a write lock context manager for use in a `with` block."""
         return self._write_transaction_impl(self.lock, acquire=self._read, release=self._write)
@@ -630,6 +658,8 @@ def _write_to_file(self, stream):
 
         This function does not do any locking or transactions.
         """
+        self._ensure_parent_directories()
+
         # map from per-spec hash code to installation record.
         installs = dict(
             (k, v.to_dict(include_fields=self.record_fields)) for k, v in self._data.items()
@@ -759,7 +789,7 @@ def _read_from_file(self, filename):
         Does not do any locking.
         """
         try:
-            with open(filename, "r", encoding="utf-8") as f:
+            with open(str(filename), "r", encoding="utf-8") as f:
                 # In the future we may use a stream of JSON objects, hence `raw_decode` for compat.
                 fdata, _ = JSONDecoder().raw_decode(f.read())
         except Exception as e:
@@ -860,11 +890,13 @@ def reindex(self):
         if self.is_upstream:
             raise UpstreamDatabaseLockingError("Cannot reindex an upstream database")
 
+        self._ensure_parent_directories()
+
         # Special transaction to avoid recursive reindex calls and to
         # ignore errors if we need to rebuild a corrupt database.
         def _read_suppress_error():
             try:
-                if os.path.isfile(self._index_path):
+                if self._index_path.is_file():
                     self._read_from_file(self._index_path)
             except CorruptDatabaseError as e:
                 tty.warn(f"Reindexing corrupt database, error was: {e}")
@@ -1007,7 +1039,7 @@ def _check_ref_counts(self):
                     % (key, found, expected, self._index_path)
                 )
 
-    def _write(self, type, value, traceback):
+    def _write(self, type=None, value=None, traceback=None):
         """Write the in-memory database index to its file path.
 
         This is a helper function called by the WriteTransaction context
@@ -1018,6 +1050,8 @@ def _write(self, type, value, traceback):
 
         This routine does no locking.
         """
+        self._ensure_parent_directories()
+
         # Do not write if exceptions were raised
         if type is not None:
             # A failure interrupted a transaction, so we should record that
@@ -1026,16 +1060,16 @@ def _write(self, type, value, traceback):
             self._state_is_inconsistent = True
             return
 
-        temp_file = self._index_path + (".%s.%s.temp" % (_getfqdn(), os.getpid()))
+        temp_file = str(self._index_path) + (".%s.%s.temp" % (_getfqdn(), os.getpid()))
 
         # Write a temporary database file them move it into place
         try:
             with open(temp_file, "w", encoding="utf-8") as f:
                 self._write_to_file(f)
-            fs.rename(temp_file, self._index_path)
+            fs.rename(temp_file, str(self._index_path))
 
             if _use_uuid:
-                with open(self._verifier_path, "w", encoding="utf-8") as f:
+                with self._verifier_path.open("w", encoding="utf-8") as f:
                     new_verifier = str(uuid.uuid4())
                     f.write(new_verifier)
                     self.last_seen_verifier = new_verifier
@@ -1048,11 +1082,11 @@ def _write(self, type, value, traceback):
 
     def _read(self):
         """Re-read Database from the data in the set location. This does no locking."""
-        if os.path.isfile(self._index_path):
+        if self._index_path.is_file():
             current_verifier = ""
             if _use_uuid:
                 try:
-                    with open(self._verifier_path, "r", encoding="utf-8") as f:
+                    with self._verifier_path.open("r", encoding="utf-8") as f:
                         current_verifier = f.read()
                 except BaseException:
                     pass
@@ -1065,7 +1099,7 @@ def _read(self):
                 self._state_is_inconsistent = False
             return
         elif self.is_upstream:
-            tty.warn("upstream not found: {0}".format(self._index_path))
+            tty.warn(f"upstream not found: {self._index_path}")
 
     def _add(
         self,
@@ -1681,7 +1715,7 @@ def query(
             )
 
         results = list(local_results) + list(x for x in upstream_results if x not in local_results)
-        results.sort()
+        results.sort()  # type: ignore[call-overload]
         return results
 
     def query_one(

lib/spack/spack/detection/common.py

@@ -15,7 +15,6 @@
 import glob
 import itertools
 import os
-import os.path
 import pathlib
 import re
 import sys

lib/spack/spack/detection/path.py

@@ -7,7 +7,6 @@
 import collections
 import concurrent.futures
 import os
-import os.path
 import re
 import sys
 import traceback

lib/spack/spack/directives.py

@@ -32,7 +32,7 @@ class OpenMpi(Package):
 """
 import collections
 import collections.abc
-import os.path
+import os
 import re
 from typing import Any, Callable, List, Optional, Tuple, Type, Union
 

lib/spack/spack/environment/environment.py

@@ -581,7 +581,7 @@ def _error_on_nonempty_view_dir(new_root):
     # Check if the target path lexists
     try:
         st = os.lstat(new_root)
-    except (IOError, OSError):
+    except OSError:
         return
 
     # Empty directories are fine
@@ -861,7 +861,7 @@ def regenerate(self, concrete_roots: List[Spec]) -> None:
         ):
             try:
                 shutil.rmtree(old_root)
-            except (IOError, OSError) as e:
+            except OSError as e:
                 msg = "Failed to remove old view at %s\n" % old_root
                 msg += str(e)
                 tty.warn(msg)
@@ -2554,7 +2554,7 @@ def is_latest_format(manifest):
     try:
         with open(manifest, encoding="utf-8") as f:
             data = syaml.load(f)
-    except (OSError, IOError):
+    except OSError:
         return True
     top_level_key = _top_level_key(data)
     changed = spack.schema.env.update(data[top_level_key])
@@ -2634,6 +2634,32 @@ def _ensure_env_dir():
 
     shutil.copy(envfile, target_manifest)
 
+    # Copy relative path includes that live inside the environment dir
+    try:
+        manifest = EnvironmentManifestFile(environment_dir)
+    except Exception:
+        # error handling for bad manifests is handled on other code paths
+        return
+
+    includes = manifest[TOP_LEVEL_KEY].get("include", [])
+    for include in includes:
+        if os.path.isabs(include):
+            continue
+
+        abspath = pathlib.Path(os.path.normpath(environment_dir / include))
+        common_path = pathlib.Path(os.path.commonpath([environment_dir, abspath]))
+        if common_path != environment_dir:
+            tty.debug(f"Will not copy relative include from outside environment: {include}")
+            continue
+
+        orig_abspath = os.path.normpath(envfile.parent / include)
+        if not os.path.exists(orig_abspath):
+            tty.warn(f"Included file does not exist; will not copy: '{include}'")
+            continue
+
+        fs.touchp(abspath)
+        shutil.copy(orig_abspath, abspath)
+
 
 class EnvironmentManifestFile(collections.abc.Mapping):
     """Manages the in-memory representation of a manifest file, and its synchronization

lib/spack/spack/environment/shell.py

@@ -10,6 +10,7 @@
 
 import spack.environment as ev
 import spack.repo
+import spack.schema.environment
 import spack.store
 from spack.util.environment import EnvironmentModifications
 
@@ -156,6 +157,11 @@ def activate(
     # MANPATH, PYTHONPATH, etc. All variables that end in PATH (case-sensitive)
     # become PATH variables.
     #
+
+    env_vars_yaml = env.manifest.configuration.get("env_vars", None)
+    if env_vars_yaml:
+        env_mods.extend(spack.schema.environment.parse(env_vars_yaml))
+
     try:
         if view and env.has_view(view):
             with spack.store.STORE.db.read_transaction():
@@ -189,6 +195,10 @@ def deactivate() -> EnvironmentModifications:
     if active is None:
         return env_mods
 
+    env_vars_yaml = active.manifest.configuration.get("env_vars", None)
+    if env_vars_yaml:
+        env_mods.extend(spack.schema.environment.parse(env_vars_yaml).reversed())
+
     active_view = os.getenv(ev.spack_env_view_var)
 
     if active_view and active.has_view(active_view):

lib/spack/spack/extensions.py

@@ -187,7 +187,7 @@ def path_for_extension(target_name: str, *, paths: List[str]) -> str:
         if name == target_name:
             return path
     else:
-        raise IOError('extension "{0}" not found'.format(target_name))
+        raise OSError('extension "{0}" not found'.format(target_name))
 
 
 def get_module(cmd_name):

lib/spack/spack/fetch_strategy.py

@@ -25,7 +25,6 @@
 import functools
 import http.client
 import os
-import os.path
 import re
 import shutil
 import urllib.error
@@ -321,9 +320,15 @@ def _fetch_urllib(self, url):
 
         request = urllib.request.Request(url, headers={"User-Agent": web_util.SPACK_USER_AGENT})
 
+        if os.path.lexists(save_file):
+            os.remove(save_file)
+
         try:
             response = web_util.urlopen(request)
-        except (TimeoutError, urllib.error.URLError) as e:
+            tty.msg(f"Fetching {url}")
+            with open(save_file, "wb") as f:
+                shutil.copyfileobj(response, f)
+        except OSError as e:
             # clean up archive on failure.
             if self.archive_file:
                 os.remove(self.archive_file)
@@ -331,14 +336,6 @@ def _fetch_urllib(self, url):
                 os.remove(save_file)
             raise FailedDownloadError(e) from e
 
-        tty.msg(f"Fetching {url}")
-
-        if os.path.lexists(save_file):
-            os.remove(save_file)
-
-        with open(save_file, "wb") as f:
-            shutil.copyfileobj(response, f)
-
         # Save the redirected URL for error messages. Sometimes we're redirected to an arbitrary
         # mirror that is broken, leading to spurious download failures. In that case it's helpful
         # for users to know which URL was actually fetched.
@@ -535,11 +532,16 @@ def __init__(self, *, url: str, checksum: Optional[str] = None, **kwargs):
     @_needs_stage
     def fetch(self):
         file = self.stage.save_filename
-        tty.msg(f"Fetching {self.url}")
+
+        if os.path.lexists(file):
+            os.remove(file)
 
         try:
             response = self._urlopen(self.url)
-        except (TimeoutError, urllib.error.URLError) as e:
+            tty.msg(f"Fetching {self.url}")
+            with open(file, "wb") as f:
+                shutil.copyfileobj(response, f)
+        except OSError as e:
             # clean up archive on failure.
             if self.archive_file:
                 os.remove(self.archive_file)
@@ -547,12 +549,6 @@ def fetch(self):
                 os.remove(file)
             raise FailedDownloadError(e) from e
 
-        if os.path.lexists(file):
-            os.remove(file)
-
-        with open(file, "wb") as f:
-            shutil.copyfileobj(response, f)
-
 
 class VCSFetchStrategy(FetchStrategy):
     """Superclass for version control system fetch strategies.

lib/spack/spack/filesystem_view.py

@@ -35,7 +35,6 @@
 
 import spack.config
 import spack.directory_layout
-import spack.paths
 import spack.projections
 import spack.relocate
 import spack.schema.projections
@@ -44,7 +43,6 @@
 import spack.util.spack_json as s_json
 import spack.util.spack_yaml as s_yaml
 from spack.error import SpackError
-from spack.hooks import sbang
 
 __all__ = ["FilesystemView", "YamlFilesystemView"]
 
@@ -91,16 +89,10 @@ def view_copy(
     if stat.S_ISLNK(src_stat.st_mode):
         spack.relocate.relocate_links(links=[dst], prefix_to_prefix=prefix_to_projection)
     elif spack.relocate.is_binary(dst):
-        spack.relocate.relocate_text_bin(binaries=[dst], prefixes=prefix_to_projection)
+        spack.relocate.relocate_text_bin(binaries=[dst], prefix_to_prefix=prefix_to_projection)
     else:
         prefix_to_projection[spack.store.STORE.layout.root] = view._root
-
-        # This is vestigial code for the *old* location of sbang.
-        prefix_to_projection[f"#!/bin/bash {spack.paths.spack_root}/bin/sbang"] = (
-            sbang.sbang_shebang_line()
-        )
-
-        spack.relocate.relocate_text(files=[dst], prefixes=prefix_to_projection)
+        spack.relocate.relocate_text(files=[dst], prefix_to_prefix=prefix_to_projection)
 
     # The os module on Windows does not have a chown function.
     if sys.platform != "win32":
@@ -435,7 +427,7 @@ def needs_file(spec, file):
             try:
                 with open(manifest_file, "r", encoding="utf-8") as f:
                     manifest = s_json.load(f)
-            except (OSError, IOError):
+            except OSError:
                 # if we can't load it, assume it doesn't know about the file.
                 manifest = {}
             return test_path in manifest
@@ -839,7 +831,7 @@ def get_spec_from_file(filename):
     try:
         with open(filename, "r", encoding="utf-8") as f:
             return spack.spec.Spec.from_yaml(f)
-    except IOError:
+    except OSError:
         return None
 
 

lib/spack/spack/hooks/absolutify_elf_sonames.py

@@ -26,7 +26,7 @@ def is_shared_library_elf(filepath):
         with open(filepath, "rb") as f:
             elf = parse_elf(f, interpreter=True, dynamic_section=True)
             return elf.has_pt_dynamic and (elf.has_soname or not elf.has_pt_interp)
-    except (IOError, OSError, ElfParsingError):
+    except (OSError, ElfParsingError):
         return False
 
 

lib/spack/spack/hooks/sbang.py

@@ -166,7 +166,7 @@ def filter_shebangs_in_directory(directory, filenames=None):
         # Only look at executable, non-symlink files.
         try:
             st = os.lstat(path)
-        except (IOError, OSError):
+        except OSError:
             continue
 
         if stat.S_ISLNK(st.st_mode) or stat.S_ISDIR(st.st_mode) or not st.st_mode & is_exe:

lib/spack/spack/installer.py

@@ -275,7 +275,7 @@ def _do_fake_install(pkg: "spack.package_base.PackageBase") -> None:
     fs.mkdirp(pkg.prefix.bin)
     fs.touch(os.path.join(pkg.prefix.bin, command))
     if sys.platform != "win32":
-        chmod = which("chmod")
+        chmod = which("chmod", required=True)
         chmod("+x", os.path.join(pkg.prefix.bin, command))
 
     # Install fake header file
@@ -814,7 +814,7 @@ def get_depflags(self, pkg: "spack.package_base.PackageBase") -> int:
         # Include build dependencies if pkg is going to be built from sources, or
         # if build deps are explicitly requested.
         if include_build_deps or not (
-            cache_only or pkg.spec.installed and not pkg.spec.dag_hash() in self.overwrite
+            cache_only or pkg.spec.installed and pkg.spec.dag_hash() not in self.overwrite
         ):
             depflag |= dt.BUILD
         if self.run_tests(pkg):

lib/spack/spack/main.py

@@ -14,7 +14,6 @@
 import io
 import operator
 import os
-import os.path
 import pstats
 import re
 import shlex
@@ -164,7 +163,7 @@ def format_help_sections(self, level):
         # lazily add all commands to the parser when needed.
         add_all_commands(self)
 
-        """Print help on subcommands in neatly formatted sections."""
+        # Print help on subcommands in neatly formatted sections.
         formatter = self._get_formatter()
 
         # Create a list of subcommand actions. Argparse internals are nasty!
@@ -729,7 +728,7 @@ def _compatible_sys_types():
     with the current host.
     """
     host_platform = spack.platforms.host()
-    host_os = str(host_platform.operating_system("default_os"))
+    host_os = str(host_platform.default_operating_system())
     host_target = archspec.cpu.host()
     compatible_targets = [host_target] + host_target.ancestors
 

lib/spack/spack/mirrors/layout.py

@@ -2,7 +2,6 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import os
-import os.path
 from typing import Optional
 
 import llnl.url

lib/spack/spack/mirrors/mirror.py

@@ -64,7 +64,7 @@ def from_local_path(path: str):
     @staticmethod
     def from_url(url: str):
         """Create an anonymous mirror by URL. This method validates the URL."""
-        if not urllib.parse.urlparse(url).scheme in supported_url_schemes:
+        if urllib.parse.urlparse(url).scheme not in supported_url_schemes:
             raise ValueError(
                 f'"{url}" is not a valid mirror URL. '
                 f"Scheme must be one of {supported_url_schemes}."

lib/spack/spack/mirrors/utils.py

@@ -2,7 +2,6 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import os
-import os.path
 import traceback
 
 import llnl.util.tty as tty

lib/spack/spack/modules/common.py

@@ -31,7 +31,7 @@
 import copy
 import datetime
 import inspect
-import os.path
+import os
 import re
 import string
 from typing import List, Optional

lib/spack/spack/modules/lmod.py

@@ -4,7 +4,7 @@
 
 import collections
 import itertools
-import os.path
+import os
 from typing import Dict, List, Optional, Tuple
 
 import llnl.util.filesystem as fs

lib/spack/spack/modules/tcl.py

@@ -5,7 +5,7 @@
 """This module implements the classes necessary to generate Tcl
 non-hierarchical modules.
 """
-import os.path
+import os
 from typing import Dict, Optional, Tuple
 
 import spack.config

lib/spack/spack/oci/opener.py

@@ -7,6 +7,7 @@
 import base64
 import json
 import re
+import socket
 import time
 import urllib.error
 import urllib.parse
@@ -382,6 +383,7 @@ def create_opener():
     """Create an opener that can handle OCI authentication."""
     opener = urllib.request.OpenerDirector()
     for handler in [
+        urllib.request.ProxyHandler(),
         urllib.request.UnknownHandler(),
         urllib.request.HTTPSHandler(context=spack.util.web.ssl_create_default_context()),
         spack.util.web.SpackHTTPDefaultErrorHandler(),
@@ -410,7 +412,7 @@ def wrapper(*args, **kwargs):
         for i in range(retries):
             try:
                 return f(*args, **kwargs)
-            except (urllib.error.URLError, TimeoutError) as e:
+            except OSError as e:
                 # Retry on internal server errors, and rate limit errors
                 # Potentially this could take into account the Retry-After header
                 # if registries support it
@@ -420,9 +422,10 @@ def wrapper(*args, **kwargs):
                         and (500 <= e.code < 600 or e.code == 429)
                     )
                     or (
-                        isinstance(e, urllib.error.URLError) and isinstance(e.reason, TimeoutError)
+                        isinstance(e, urllib.error.URLError)
+                        and isinstance(e.reason, socket.timeout)
                     )
-                    or isinstance(e, TimeoutError)
+                    or isinstance(e, socket.timeout)
                 ):
                     # Exponential backoff
                     sleep(2**i)