Merge branch 'develop' into f/env-location

etc/spack/defaults/config.yaml

@@ -19,7 +19,7 @@ config:
   install_tree:
     root: $spack/opt/spack
     projections:
-      all: "${ARCHITECTURE}/${COMPILERNAME}-${COMPILERVER}/${PACKAGE}-${VERSION}-${HASH}"
+      all: "{architecture}/{compiler.name}-{compiler.version}/{name}-{version}-{hash}"
     # install_tree can include an optional padded length (int or boolean)
     # default is False (do not pad)
     # if padded_length is True, Spack will pad as close to the system max path
@@ -218,4 +218,8 @@ config:
 
   # Number of seconds a buildcache's index.json is cached locally before probing
   # for updates, within a single Spack invocation. Defaults to 10 minutes.
-  binary_index_ttl: 600
+  binary_index_ttl: 600
+
+  flags:
+    # Whether to keep -Werror flags active in package builds.
+    keep_werror: 'none'