## Motivation
Our parser grew to be quite complex, with a 2-state lexer and logic in the parser
that has up to 5 levels of nested conditionals. In the future, to turn compilers into
proper dependencies, we'll have to increase the complexity further as we foresee
the need to add:
1. Edge attributes
2. Spec nesting
to the spec syntax (see https://github.com/spack/seps/pull/5 for an initial discussion of
those changes). The main attempt here is thus to _simplify the existing code_ before
we start extending it later. We try to do that by adopting a different token granularity,
and by using more complex regexes for tokenization. This allow us to a have a "flatter"
encoding for the parser. i.e., it has fewer nested conditionals and a near-trivial lexer.
There are places, namely in `VERSION`, where we have to use negative lookahead judiciously
to avoid ambiguity. Specifically, this parse is ambiguous without `(?!\s*=)` in `VERSION_RANGE`
and an extra final `\b` in `VERSION`:
```
@ 1.2.3 : develop # This is a version range 1.2.3:develop
@ 1.2.3 : develop=foo # This is a version range 1.2.3: followed by a key-value pair
```
## Differences with the previous parser
~There are currently 2 known differences with the previous parser, which have been added on purpose:~
- ~No spaces allowed after a sigil (e.g. `foo @ 1.2.3` is invalid while `foo @1.2.3` is valid)~
- ~`/<hash> @1.2.3` can be parsed as a concrete spec followed by an anonymous spec (before was invalid)~
~We can recover the previous behavior on both ones but, especially for the second one, it seems the current behavior in the PR is more consistent.~
The parser is currently 100% backward compatible.
## Error handling
Being based on more complex regexes, we can possibly improve error
handling by adding regexes for common issues and hint users on that.
I'll leave that for a following PR, but there's a stub for this approach in the PR.
## Performance
To be sure we don't add any performance penalty with this new encoding, I measured:
```console
$ spack python -m timeit -s "import spack.spec" -c "spack.spec.Spec(<spec>)"
```
for different specs on my machine:
* **Spack:** 0.20.0.dev0 (c9db4e50ba045f5697816187accaf2451cb1aae7)
* **Python:** 3.8.10
* **Platform:** linux-ubuntu20.04-icelake
* **Concretizer:** clingo
results are:
| Spec | develop | this PR |
| ------------- | ------------- | ------- |
| `trilinos` | 28.9 usec | 13.1 usec |
| `trilinos @1.2.10:1.4.20,2.0.1` | 131 usec | 120 usec |
| `trilinos %gcc` | 44.9 usec | 20.9 usec |
| `trilinos +foo` | 44.1 usec | 21.3 usec |
| `trilinos foo=bar` | 59.5 usec | 25.6 usec |
| `trilinos foo=bar ^ mpich foo=baz` | 120 usec | 82.1 usec |
so this new parser seems to be consistently faster than the previous one.
## Modifications
In this PR we just substituted the Spec parser, which means:
- [x] Deleted in `spec.py` the `SpecParser` and `SpecLexer` classes. deleted `spack/parse.py`
- [x] Added a new parser in `spack/parser.py`
- [x] Hooked the new parser in all the places the previous one was used
- [x] Adapted unit tests in `test/spec_syntax.py`
## Possible future improvements
Random thoughts while working on the PR:
- Currently we transform hashes and files into specs during parsing. I think
we might want to introduce an additional step and parse special objects like
a `FileSpec` etc. in-between parsing and concretization.
* Enable hdf5 build (including +mpi) on Windows
* This includes updates to hdf5 dependencies openssl (minor edit) and
bzip2 (more-extensive edits)
* Add binary-based installation of msmpi (this is currently the only
supported MPI implementation in Spack for Windows). Note that this
does not install to the Spack-specified prefix. This implementation
will be replaced with a source-based implementation
Co-authored-by: John Parent <john.parent@kitware.com>
I'm finding I often want the date in my paths and it would be nice if spack had a config variable for this.
Co-authored-by: Tamara Dahlgren <35777542+tldahlgren@users.noreply.github.com>
* Remove CI jobs related to Python 2.7
* Remove Python 2.7 specific code from Spack core
* Remove externals for Python 2 only
* Remove llnl.util.compat
Environments and environment views have taken over the role of `spack activate/deactivate`, and we should deprecate these commands for several reasons:
- Global activation is a really poor idea:
- Install prefixes should be immutable; since they can have multiple, unrelated dependents; see below
- Added complexity elsewhere: verification of installations, tarballs for build caches, creation of environment views of packages with unrelated extensions "globally activated"... by removing the feature, it gets easier for people to contribute, and we'd end up with fewer bugs due to edge cases.
- Environment accomplish the same thing for non-global "activation" i.e. `spack view`, but better.
Also we write in the docs:
```
However, Spack global activations have two potential drawbacks:
#. Activated packages that involve compiled C extensions may still
need their dependencies to be loaded manually. For example,
``spack load openblas`` might be required to make ``py-numpy``
work.
#. Global activations "break" a core feature of Spack, which is that
multiple versions of a package can co-exist side-by-side. For example,
suppose you wish to run a Python package in two different
environments but the same basic Python --- one with
``py-numpy@1.7`` and one with ``py-numpy@1.8``. Spack extensions
will not support this potential debugging use case.
```
Now that environments are established and views can take over the role of activation
non-destructively, we can remove global activation/deactivation.
`spack env create` enables a view by default (in a weird hidden
directory, but well...). This is asking for trouble with the other
default of `concretizer:unify:false`, since having different flavors of
the same spec in an environment, leads to collision errors when
generating the view.
A change of defaults would improve user experience:
However, `unify:true` makes most sense, since any time the issue is
brought up in Slack, the user changes the concretization config, since
it wasn't the intention to have different flavors of the same spec, and
install times are decreased.
Further we improve the docs and drop the duplicate root spec limitation
Argparse started raising ArgumentError exceptions
when the same parser is added twice. Therefore, we
perform the addition only if the parser is not there
already
Port match syntax to our unparser
A user may want to set some attributes on a package without actually modifying the package (e.g. if they want to git pull updates to the package without conflicts). This PR adds a per-package configuration section called "set", which is a dictionary of attribute names to desired values. For example:
packages:
openblas:
package_attributes:
submodules: true
git: "https://github.com/myfork/openblas"
in this case, the package will always retrieve git submodules, and will use an alternate location for the git repo.
While git, url, and submodules are the attributes for which we envision the most usage, this allows any attribute to be overridden, and the acceptable values are any value parseable from yaml.
Adds another post install hook that loops over the install prefix, looking for shared libraries type of ELF files, and sets the soname to their own absolute paths.
The idea being, whenever somebody links against those libraries, the linker copies the soname (which is the absolute path to the library) as a "needed" library, so that at runtime the dynamic loader realizes the needed library is a path which should be loaded directly without searching.
As a result:
1. rpaths are not used for the fixed/static list of needed libraries in the dynamic section (only for _actually_ dynamically loaded libraries through `dlopen`), which largely solves the issue that Spack's rpaths are a heuristic (`<prefix>/lib` and `<prefix>/lib64` might not be where libraries really are...)
2. improved startup times (no library search required)
Currently, compiler flags and variants are inconsistent: compiler flags set for a
package are inherited by its dependencies, while variants are not. We should have these
be consistent by allowing for inheritance to be enabled or disabled for both variants
and compiler flags.
- [x] Make new (spec language) operators
- [x] Apply operators to variants and compiler flags
- [x] Conflicts currently result in an unsatisfiable spec
(i.e., you can't propagate two conflicting values)
What I propose is using two of the currently used sigils to symbolized that the variant
or compiler flag will be inherited:
Example syntax:
- `package ++variant`
enabled variant that will be propagated to dependencies
- `package +variant`
enabled variant that will NOT be propagated to dependencies
- `package ~~variant`
disabled variant that will be propagated to dependencies
- `package ~variant`
disabled variant that will NOT be propagated to dependencies
- `package cflags==True`
`cflags` will be propagated to dependencies
- `package cflags=True`
`cflags` will NOT be propagated to dependencies
Syntax for string-valued variants is similar to compiler flags.
The `spack info <package>` command does not show the `Virtual Packages:` output unless the `--virtuals` command option is passed. Before this changes, the information that the command is supposed to be illustrating is not shown in the example and is confusing.
This commit extends the DSL that can be used in packages
to allow declaring that a package uses different build-systems
under different conditions.
It requires each spec to have a `build_system` single valued
variant. The variant can be used in many context to query, manipulate
or select the build system associated with a concrete spec.
The knowledge to build a package has been moved out of the
PackageBase hierarchy, into a new Builder hierarchy. Customization
of the default behavior for a given builder can be obtained by
coding a new derived builder in package.py.
The "run_after" and "run_before" decorators are now applied to
methods on the builder. They can also incorporate a "when="
argument to specify that a method is run only when certain
conditions apply.
For packages that do not define their own builder, forwarding logic
is added between the builder and package (methods not found in one
will be retrieved from the other); this PR is expected to be fully
backwards compatible with unmodified packages that use a single
build system.
* Docs: Getting Started Dependencies
Finally document what one needs to install to use Spack on
Linux and Mac :-)
With <3 for minimal container users and my colleagues with
their fancy Macs.
* Debian Update Packages: GCC, Python
- build-essential: includes gcc, g++ (thx Cory)
- Python: add python3-venv, python3-distutils (thx Pradyun)
* Add RHEL8 Dependencies
fixes#31484
Before this change if anything was matching an external
condition, it was considered "external" and thus something
to be "built".
This was happening in particular to external packages
that were re-read from the DB, which then couldn't be
reused, causing the problems shown in #31484.
This PR fixes the issue by excluding specs with a
"hash" from being considered "external"
* Test that users have a way to select a virtual
This ought to be solved by extending the "require"
attribute to virtual packages, so that one can:
```yaml
mpi:
require: 'multi-provider-mpi'
```
* Prevent conflicts to be enforced on specs that can be reused.
* Rename the "external_only" fact to "buildable_false", to better reflect its origin
* Preliminary support for include URLs in spack.yaml (environment) files
This commit adds support in environments for external configuration files obtained from a URL with a preference for grabbing raw text from GitHub and gitlab for efficient downloads of the relevant files. The URL can also be a link to a directory that contains multiple configuration files.
Remote configuration files are retrieved and cached for the environment. Configuration files with the same name will not be overwritten once cached.
Extend the semantics of package requirements to
allow using them also under a virtual package
attribute in packages.yaml
These requirements are enforced whenever that
virtual spec is present in the DAG.
Allow users to express default requirements in packages.yaml.
These requirements are overridden if more specific requirements
are present for a given package.
