v0.22.0 (2024-05-12)

v0.22.0 is a major feature release.

Features in this release

Compiler dependencies

We are in the process of making compilers proper dependencies in Spack, and a number of changes in v0.22 support that effort. You may notice nodes in your dependency graphs for compiler runtime libraries like gcc-runtime or libgfortran, and you may notice that Spack graphs now include libc. We've also begun moving compiler configuration from compilers.yaml to packages.yaml to make it consistent with other externals. We are trying to do this with the least disruption possible, so your existing compilers.yaml files should still work. We expect to be done with this transition by the v0.23 release in November.
- #41104: Packages compiled with %gcc on Linux, macOS and FreeBSD now depend on a new package gcc-runtime, which contains a copy of the shared compiler runtime libraries. This enables gcc runtime libraries to be installed and relocated when using a build cache. When building minimal Spack-generated container images it is no longer necessary to install libgfortran, libgomp etc. using the system package manager.
- #42062: Packages compiled with %oneapi now depend on a new package intel-oneapi-runtime. This is similar to gcc-runtime, and the runtimes can provide virtuals and compilers can inject dependencies on virtuals into compiled packages. This allows us to model library soname compatibility and allows compilers like %oneapi to provide virtuals like sycl (which can also be provided by standalone libraries). Note that until we have an agreement in place with intel, Intel packages are marked redistribute(source=False, binary=False) and must be downloaded outside of Spack.
- #43272: changes to the optimization criteria of the solver improve the hit-rate of buildcaches by a fair amount. The solver more relaxed compatibility rules and will not try to strictly match compilers or targets of reused specs. Users can still enforce the previous strict behavior with require: sections in packages.yaml. Note that to enforce correct linking, Spack will not reuse old %gcc and %oneapi specs that do not have the runtime libraries as a dependency.
- #43539: Spack will reuse specs built with compilers that are not explicitly configured in compilers.yaml. Because we can now keep runtime libraries in build cache, we do not require you to also have a local configured compiler to use the runtime libraries. This improves reuse in buildcaches and avoids conflicts with OS updates that happen underneath Spack.
- #43190: binary compatibility on linux is now based on the libc version, instead of on the os tag. Spack builds now detect the host libc (glibc or musl) and add it as an implicit external node in the dependency graph. Binaries with a libc with the same name and a version less than or equal to that of the detected libc can be reused. This is only on linux, not macos or Windows.
- #43464: each package that can provide a compiler is now detectable using spack external find. External packages defining compiler paths are effectively used as compilers, and spack external find -t compiler can be used as a substitute for spack compiler find. More details on this transition are in the docs
Improved spack find UI for Environments

If you're working in an enviroment, you likely care about:
- What are the roots
- Which ones are installed / not installed
- What's been added that still needs to be concretized
We've tweaked spack find in environments to show this information much more clearly. Installation status is shown next to each root, so you can see what is installed. Roots are also shown in bold in the list of installed packages. There is also a new option for spack find -r / --only-roots that will only show env roots, if you don't want to look at all the installed specs.

More details in #42334.
Improved command-line string quoting

We are making some breaking changes to how Spack parses specs on the CLI in order to respect shell quoting instead of trying to fight it. If you (sadly) had to write something like this on the command line:
```
spack install zlib cflags=\"-O2 -g\"
```
That will now result in an error, but you can now write what you probably expected to work in the first place:
```
spack install zlib cflags="-O2 -g"
```
Quoted can also now include special characters, so you can supply flags like:
```
spack intall zlib ldflags='-Wl,-rpath=$ORIGIN/_libs'
```
To reduce ambiguity in parsing, we now require that you not put spaces around = and == when for flags or variants. This would not have broken before but will now result in an error:
```
spack install zlib cflags = "-O2 -g"
```
More details and discussion in #30634.
Revert default spack install behavior to --reuse

We changed the default concretizer behavior from --reuse to --reuse-deps in #30990 (in v0.20), which meant that every spack install invocation would attempt to build a new version of the requested package / any environment roots. While this is a common ask for upgrading and for developer workflows, we don't think it should be the default for a package manager.

We are going to try to stick to this policy:
1. Prioritize reuse and build as little as possible by default.
2. Only upgrade or install duplicates if they are explicitly asked for, or if there is a known security issue that necessitates an upgrade.
With the install command you now have three options:
- --reuse (default): reuse as many existing installations as possible.
- --reuse-deps / --fresh-roots: upgrade (freshen) roots but reuse dependencies if possible.
- --fresh: install fresh versions of requested packages (roots) and their dependencies.
We've also introduced --fresh-roots as an alias for --reuse-deps to make it more clear that it may give you fresh versions. More details in #41302 and #43988.
More control over reused specs

You can now control which packages to reuse and how. There is a new concretizer:reuse config option, which accepts the following properties:
- roots: true to reuse roots, false to reuse just dependencies
- exclude: list of constraints used to select which specs not to reuse
- include: list of constraints used to select which specs to reuse
- from: list of sources for reused specs (some combination of local, buildcache, or external)
For example, to reuse only specs compiled with GCC, you could write:
```
concretizer:
   reuse:
     roots: true
     include:
     - "%gcc"
```
Or, if openmpi must be used from externals, and it must be the only external used:
```
concretizer:
  reuse:
    roots: true
    from:
    - type: local
      exclude: ["openmpi"]
    - type: buildcache
      exclude: ["openmpi"]
    - type: external
      include: ["openmpi"]
```

New redistribute() directive

Some packages can't be redistributed in source or binary form. We need an explicit way to say that in a package.

Now there is a redistribute() directive so that package authors can write:

class MyPackage(Package):
    redistribute(source=False, binary=False)

Like other directives, this works with when=:

class MyPackage(Package):
    # 12.0 and higher are proprietary
    redistribute(source=False, binary=False, when="@12.0:")

    # can't redistribute when we depend on some proprietary dependency
    redistribute(source=False, binary=False, when="^proprietary-dependency")

New commands, options, and directives

Allow packages to be pushed to build cache after install from source (#42423)
spack develop: stage build artifacts in same root as non-dev builds #41373
- Don't delete spack develop build artifacts after install (#43424)
spack find: add options for local/upstream only (#42999)
spack logs: print log files for packages (either partially built or installed) (#42202)
patch: support reversing patches (#43040)
develop: Add -b/--build-directory option to set build_directory package attribute (#39606)
spack list: add --namesapce / --repo option (#41948)
directives: add checked_by field to license(), add some license checks
spack gc: add options for environments and build dependencies (#41731)
Add --create to spack env activate (#40896)

Performance improvements

environment.py: fix excessive re-reads (#43746)
ruamel yaml: fix quadratic complexity bug (#43745)
Refactor to improve spec format speed (#43712)
Do not acquire a write lock on the env post install if no views (#43505)
asp.py: fewer calls to spec.copy() (#43715)
spec.py: early return in __str__
avoid jinja2 import at startup unless needed (#43237)

Other new features of note

archspec: update to v0.2.4: support for Windows, bugfixes for neoverse-v1 and neoverse-v2 detection.
spack config get/blame: with no args, show entire config
spack env create <env>: dir if dir-like (#44024)
ASP-based solver: update os compatibility for macOS (#43862)
Add handling of custom ssl certs in urllib ops (#42953)
Add ability to rename environments (#43296)
Add config option and compiler support to reuse across OS's (#42693)
Support for prereleases (#43140)
Only reuse externals when configured (#41707)
Environments: Add support for including views (#42250)

Binary caches

Build cache: make signed/unsigned a mirror property (#41507)
tools stack

Removals, deprecations, and syntax changes

remove dpcpp compiler and package (#43418)
spack load: remove --only argument (#42120)

Notable Bugfixes

repo.py: drop deleted packages from provider cache (#43779)
Allow + in module file names (#41999)
cmd/python: use runpy to allow multiprocessing in scripts (#41789)
Show extension commands with spack -h (#41726)
Support environment variable expansion inside module projections (#42917)
Alert user to failed concretizations (#42655)
shell: fix zsh color formatting for PS1 in environments (#39497)
spack mirror create --all: include patches (#41579)

Spack community stats

7,994 total packages; 525 since v0.21.0
- 178 new Python packages, 5 new R packages
358 people contributed to this release
- 344 committers to packages
- 45 committers to core

v0.21.2 (2024-03-01)

Bugfixes

Containerize: accommodate nested or pre-existing spack-env paths (#41558)
Fix setup-env script, when going back and forth between instances (#40924)
Fix using fully-qualified namespaces from root specs (#41957)
Fix a bug when a required provider is requested for multiple virtuals (#42088)
OCI buildcaches:
- only push in parallel when forking (#42143)
- use pickleable errors (#42160)
Fix using sticky variants in externals (#42253)
Fix a rare issue with conditional requirements and multi-valued variants (#42566)

Package updates

rust: add v1.75, rework a few variants (#41161,#41903)
py-transformers: add v4.35.2 (#41266)
mgard: fix OpenMP on AppleClang (#42933)

v0.21.1 (2024-01-11)

New features

Add support for reading buildcaches created by Spack v0.22 (#41773)

Bugfixes

spack graph: fix coloring with environments (#41240)
spack info: sort variants in --variants-by-name (#41389)
Spec.format: error on old style format strings (#41934)
ASP-based solver:
- fix infinite recursion when computing concretization errors (#41061)
- don't error for type mismatch on preferences (#41138)
- don't emit spurious debug output (#41218)
Improve the error message for deprecated preferences (#41075)
Fix MSVC preview version breaking clingo build on Windows (#41185)
Fix multi-word aliases (#41126)
Add a warning for unconfigured compiler (#41213)
environment: fix an issue with deconcretization/reconcretization of specs (#41294)
buildcache: don't error if a patch is missing, when installing from binaries (#41986)
Multiple improvements to unit-tests (#41215,#41369,#41495,#41359,#41361,#41345,#41342,#41308,#41226)

Package updates

root: add a webgui patch to address security issue (#41404)
BerkeleyGW: update source urls (#38218)

v0.21.0 (2023-11-11)

v0.21.0 is a major feature release.

Features in this release

Better error messages with condition chaining

In v0.18, we added better error messages that could tell you what problem happened, but they couldn't tell you why it happened. 0.21 adds condition chaining to the solver, and Spack can now trace back through the conditions that led to an error and build a tree of causes potential causes and where they came from. For example:

$ spack solve hdf5 ^cmake@3.0.1
==> Error: concretization failed for the following reasons:

   1. Cannot satisfy 'cmake@3.0.1'
   2. Cannot satisfy 'cmake@3.0.1'
        required because hdf5 ^cmake@3.0.1 requested from CLI
   3. Cannot satisfy 'cmake@3.18:' and 'cmake@3.0.1
        required because hdf5 ^cmake@3.0.1 requested from CLI
        required because hdf5 depends on cmake@3.18: when @1.13:
          required because hdf5 ^cmake@3.0.1 requested from CLI
   4. Cannot satisfy 'cmake@3.12:' and 'cmake@3.0.1
        required because hdf5 depends on cmake@3.12:
          required because hdf5 ^cmake@3.0.1 requested from CLI
        required because hdf5 ^cmake@3.0.1 requested from CLI

More details in #40173.

OCI build caches

You can now use an arbitrary OCI registry as a build cache:
```
$ spack mirror add my_registry oci://user/image # Dockerhub
$ spack mirror add my_registry oci://ghcr.io/haampie/spack-test # GHCR
$ spack mirror set --push --oci-username ... --oci-password ... my_registry  # set login creds
$ spack buildcache push my_registry [specs...]
```
And you can optionally add a base image to get runnable images:
```
$ spack buildcache push --base-image ubuntu:23.04 my_registry python
Pushed ... as [image]:python-3.11.2-65txfcpqbmpawclvtasuog4yzmxwaoia.spack

$ docker run --rm -it [image]:python-3.11.2-65txfcpqbmpawclvtasuog4yzmxwaoia.spack
```
This creates a container image from the Spack installations on the host system, without the need to run spack install from a Dockerfile or sif file. It also addresses the inconvenience of losing binaries of dependencies when RUN spack install fails inside docker build.

Further, the container image layers and build cache tarballs are the same files. This means that spack install and docker pull use the exact same underlying binaries. If you previously used spack install inside of docker build, this feature helps you save storage by a factor two.

More details in #38358.
Multiple versions of build dependencies

Increasingly, complex package builds require multiple versions of some build dependencies. For example, Python packages frequently require very specific versions of setuptools, cython, and sometimes different physics packages require different versions of Python to build. The concretizer enforced that every solve was unified, i.e., that there only be one version of every package. The concretizer now supports "duplicate" nodes for build dependencies, but enforces unification through transitive link and run dependencies. This will allow it to better resolve complex dependency graphs in ecosystems like Python, and it also gets us very close to modeling compilers as proper dependencies.

This change required a major overhaul of the concretizer, as well as a number of performance optimizations. See #38447, #39621.
Cherry-picking virtual dependencies

You can now select only a subset of virtual dependencies from a spec that may provide more. For example, if you want mpich to be your mpi provider, you can be explicit by writing:
```
hdf5 ^[virtuals=mpi] mpich
```
Or, if you want to use, e.g., intel-parallel-studio for blas along with an external lapack like openblas, you could write:
```
strumpack ^[virtuals=mpi] intel-parallel-studio+mkl ^[virtuals=lapack] openblas
```
The virtuals=mpi is an edge attribute, and dependency edges in Spack graphs now track which virtuals they satisfied. More details in #17229 and #35322.

Note for packaging: in Spack 0.21 spec.satisfies("^virtual") is true if and only if the package specifies depends_on("virtual"). This is different from Spack 0.20, where depending on a provider implied depending on the virtual provided. See #41002 for an example where ^mkl was being used to test for several mkl providers in a package that did not depend on mkl.
License directive

Spack packages can now have license metadata, with the new license() directive:
```
    license("Apache-2.0")
```
Licenses use SPDX identifiers, and you can use SPDX expressions to combine them:
```
    license("Apache-2.0 OR MIT")
```
Like other directives in Spack, it's conditional, so you can handle complex cases like Spack itself:
```
   license("LGPL-2.1", when="@:0.11")
   license("Apache-2.0 OR MIT", when="@0.12:")
```
More details in #39346, #40598.
spack deconcretize command

We are getting close to having a spack update command for environments, but we're not quite there yet. This is the next best thing. spack deconcretize gives you control over what you want to update in an already concrete environment. If you have an environment built with, say, meson, and you want to update your meson version, you can run:
```
spack deconcretize meson
```
and have everything that depends on meson rebuilt the next time you run spack concretize. In a future Spack version, we'll handle all of this in a single command, but for now you can use this to drop bits of your lockfile and resolve your dependencies again. More in #38803.
UI Improvements

The venerable spack info command was looking shabby compared to the rest of Spack's UI, so we reworked it to have a bit more flair. spack info now makes much better use of terminal space and shows variants, their values, and their descriptions much more clearly. Conditional variants are grouped separately so you can more easily understand how packages are structured. More in #40998.

spack checksum now allows you to filter versions from your editor, or by version range. It also notifies you about potential download URL changes. See #40403.
Environments can include definitions

Spack did not previously support using include: with The definitions section of an environment, but now it does. You can use this to curate lists of specs and more easily reuse them across environments. See #33960.
Aliases

You can now add aliases to Spack commands in config.yaml, e.g. this might enshrine your favorite args to spack find as spack f:
```
config:
  aliases:
    f: find -lv
```
See #17229.
Improved autoloading of modules

Spack 0.20 was the first release to enable autoloading of direct dependencies in module files.

The downside of this was that module avail and module load tab completion would show users too many modules to choose from, and many users disabled generating modules for dependencies through exclude_implicits: true. Further, it was necessary to keep hashes in module names to avoid file name clashes.

In this release, you can start using hide_implicits: true instead, which exposes only explicitly installed packages to the user, while still autoloading dependencies. On top of that, you can safely use hash_length: 0, as this config now only applies to the modules exposed to the user -- you don't have to worry about file name clashes for hidden dependencies.

Note: for tcl this feature requires Modules 4.7 or higher

Updated container labeling

Nightly Docker images from the develop branch will now be tagged as :develop and :nightly. The :latest tag is no longer associated with :develop, but with the latest stable release. Releases will be tagged with :{major}, :{major}.{minor} and :{major}.{minor}.{patch}. ubuntu:18.04 has also been removed from the list of generated Docker images, as it is no longer supported. See #40593.

Other new commands and directives

spack env activate without arguments now loads a default environment that you do not have to create (#40756).
spack find -H / --hashes: a new shortcut for piping spack find output to other commands (#38663)
Add spack checksum --verify, fix --add (#38458)
New default_args context manager factors out common args for directives (#39964)
spack compiler find --[no]-mixed-toolchain lets you easily mix clang and gfortran on Linux (#40902)

Performance improvements

spack external find execution is now much faster (#39843)
spack location -i now much faster on success (#40898)
Drop redundant rpaths post install (#38976)
ASP-based solver: avoid cycles in clingo using hidden directive (#40720)
Fix multiple quadratic complexity issues in environments (#38771)

Other new features of note

archspec: update to v0.2.2, support for Sapphire Rapids, Power10, Neoverse V2 (#40917)
Propagate variants across nodes that don't have that variant (#38512)
Implement fish completion (#29549)
Can now distinguish between source/binary mirror; don't ping mirror.spack.io as much (#34523)
Improve status reporting on install (add [n/total] display) (#37903)

Windows

This release has the best Windows support of any Spack release yet, with numerous improvements and much larger swaths of tests passing:

MSVC and SDK improvements (#37711, #37930, #38500, #39823, #39180)
Windows external finding: update default paths; treat .bat as executable on Windows (#39850)
Windows decompression: fix removal of intermediate file (#38958)
Windows: executable/path handling (#37762)
Windows build systems: use ninja and enable tests (#33589)
Windows testing (#36970, #36972, #36973, #36840, #36977, #36792, #36834, #34696, #36971)
Windows PowerShell support (#39118, #37951)
Windows symlinking and libraries (#39933, #38599, #34701, #38578, #34701)

Notable refactors

User-specified flags take precedence over others in Spack compiler wrappers (#37376)
Improve setup of build, run, and test environments (#35737, #40916)
make is no longer a required system dependency of Spack (#40380)
Support Python 3.12 (#40404, #40155, #40153)
docs: Replace package list with packages.spack.io (#40251)
Drop Python 2 constructs in Spack (#38720, #38718, #38703)

Binary cache and stack updates

e4s arm stack: duplicate and target neoverse v1 (#40369)
Add macOS ML CI stacks (#36586)
E4S Cray CI Stack (#37837)
e4s cray: expand spec list (#38947)
e4s cray sles ci: expand spec list (#39081)

Removals, deprecations, and syntax changes

ASP: targets, compilers and providers soft-preferences are only global (#31261)
Parser: fix ambiguity with whitespace in version ranges (#40344)
Module file generation is disabled by default; you'll need to enable it to use it (#37258)
Remove deprecated "extra_instructions" option for containers (#40365)
Stand-alone test feature deprecation postponed to v0.22 (#40600)
buildcache push: make --allow-root the default and deprecate the option (#38878)

Notable Bugfixes

Bugfix: propagation of multivalued variants (#39833)
Allow / in git versions (#39398)
Fetch & patch: actually acquire stage lock, and many more issues (#38903)
Environment/depfile: better escaping of targets with Git versions (#37560)
Prevent "spack external find" to error out on wrong permissions (#38755)
lmod: allow core compiler to be specified with a version range (#37789)

Spack community stats

7,469 total packages, 303 new since v0.20.0
- 150 new Python packages
- 34 new R packages
353 people contributed to this release
- 336 committers to packages
- 65 committers to core

v0.20.3 (2023-10-31)

Bugfixes

Fix a bug where spack mirror set-url would drop configured connection info (reverts #34210)
Fix a minor issue with package hash computation for Python 3.12 (#40328)

v0.20.2 (2023-10-03)

Features in this release

Spack now supports Python 3.12 (#40155)

Bugfixes

Improve escaping in Tcl module files (#38375)
Make repo cache work on repositories with zero mtime (#39214)
Ignore errors for newer, incompatible buildcache version (#40279)
Print an error when git is required, but missing (#40254)
Ensure missing build dependencies get installed when using spack install --overwrite (#40252)
Fix an issue where Spack freezes when the build process unexpectedly exits (#39015)
Fix a bug where installation failures cause an unrelated NameError to be thrown (#39017)
Fix an issue where Spack package versions would be incorrectly derived from git tags (#39414)
Fix a bug triggered when file locking fails internally (#39188)
Prevent "spack external find" to error out when a directory cannot be accessed (#38755)
Fix multiple performance regressions in environments (#38771)
Add more ignored modules to pyproject.toml for mypy (#38769)

v0.20.1 (2023-07-10)

Spack Bugfixes

Spec removed from an environment where not actually removed if --force was not given (#37877)
Speed-up module file generation (#37739)
Hotfix for a few recipes that treat CMake as a link dependency (#35816)
Fix re-running stand-alone test a second time, which was getting a trailing spurious failure (#37840)
Fixed reading JSON manifest on Cray, reporting non-concrete specs (#37909)
Fixed a few bugs when generating Dockerfiles from Spack (#37766,#37769)
Fixed a few long-standing bugs when generating module files (#36678,#38347,#38465,#38455)
Fixed issues with building Python extensions using an external Python (#38186)
Fixed compiler removal from command line (#38057)
Show external status as [e] (#33792)
Backported archspec fixes (#37793)
Improved a few error messages (#37791)

v0.20.0 (2023-05-21)

v0.20.0 is a major feature release.

Features in this release

requires() directive and enhanced package requirements

We've added some more enhancements to requirements in Spack (#36286).

There is a new requires() directive for packages. requires() is the opposite of conflicts(). You can use it to impose constraints on this package when certain conditions are met:
```
requires(
    "%apple-clang",
    when="platform=darwin",
    msg="This package builds only with clang on macOS"
)
```
More on this in the docs.

You can also now add a when: clause to requires: in your packages.yaml configuration or in an environment:
```
packages:
  openmpi:
    require:
    - any_of: ["%gcc"]
      when: "@:4.1.4"
      message: "Only OpenMPI 4.1.5 and up can build with fancy compilers"
```
More details can be found here
Exact versions

Spack did not previously have a way to distinguish a version if it was a prefix of some other version. For example, @3.2 would match 3.2, 3.2.1, 3.2.2, etc. You can now match exactly 3.2 with @=3.2. This is useful, for example, if you need to patch only the 3.2 version of a package. The new syntax is described in the docs.

Generally, when writing packages, you should prefer to use ranges like @3.2 over the specific versions, as this allows the concretizer more leeway when selecting versions of dependencies. More details and recommendations are in the packaging guide.

See #36273 for full details on the version refactor.
New testing interface

Writing package tests is now much simpler with a new test interface.

Writing a test is now as easy as adding a method that starts with test_:
```
class MyPackage(Package):
    ...

    def test_always_fails(self):
        """use assert to always fail"""
        assert False

    def test_example(self):
        """run installed example"""
        example = which(self.prefix.bin.example)
        example()
```
You can use Python's native assert statement to implement your checks -- no more need to fiddle with run_test or other test framework methods. Spack will introspect the class and run test_* methods when you run spack test,
More stable concretization
- Now, spack concretize will only concretize the new portions of the environment and will not change existing parts of an environment unless you specify --force. This has always been true for unify:false, but not for unify:true and unify:when_possible environments. Now it is true for all of them (#37438, #37681).
- The concretizer has a new --reuse-deps argument that only reuses dependencies. That is, it will always treat the roots of your environment as it would with --fresh. This allows you to upgrade just the roots of your environment while keeping everything else stable (#30990).
Weekly develop snapshot releases

Since last year, we have maintained a buildcache of develop at https://binaries.spack.io/develop, but the cache can grow to contain so many builds as to be unwieldy. When we get a stable develop build, we snapshot the release and add a corresponding tag the Spack repository. So, you can use a stack from a specific day. There are now tags in the spack repository like:
- develop-2023-05-14
- develop-2023-05-18
that correspond to build caches like:
- https://binaries.spack.io/develop-2023-05-14/e4s
- https://binaries.spack.io/develop-2023-05-18/e4s
We plan to store these snapshot releases weekly.
Specs in buildcaches can be referenced by hash.
- Previously, you could run spack buildcache list and see the hashes in buildcaches, but referring to them by hash would fail.
- You can now run commands like spack spec and spack install and refer to buildcache hashes directly, e.g. spack install /abc123 (#35042)
New package and buildcache index websites

Our public websites for searching packages have been completely revamped and updated. You can check them out here:
- Package Index: https://packages.spack.io
- Buildcache Index: https://cache.spack.io
Both are searchable and more interactive than before. Currently major releases are shown; UI for browsing develop snapshots is coming soon.
Default CMake and Meson build types are now Release

Spack has historically defaulted to building with optimization and debugging, but packages like llvm can be enormous with debug turned on. Our default build type for all Spack packages is now Release (#36679, #37436). This has a number of benefits:
- much smaller binaries;
- higher default optimization level; and
- defining NDEBUG disables assertions, which may lead to further speedups.
You can still get the old behavior back through requirements and package preferences.

Other new commands and directives

spack checksum can automatically add new versions to package (#24532)
new command: spack pkg grep to easily search package files (#34388)
New maintainers directive (#35083)
Add spack buildcache push (alias to buildcache create) (#34861)
Allow using -j to control the parallelism of concretization (#37608)
Add --exclude option to 'spack external find' (#35013)

Other new features of note

editing: add higher-precedence SPACK_EDITOR environment variable
Many YAML formatting improvements from updating ruamel.yaml to the latest version supporting Python 3.6. (#31091, #24885, #37008).
Requirements and preferences should not define (non-git) versions (#37687, #37747)
Environments now store spack version/commit in spack.lock (#32801)
User can specify the name of the packages subdirectory in repositories (#36643)
Add container images supporting RHEL alternatives (#36713)
make version(...) kwargs explicit (#36998)

Notable refactors

buildcache create: reproducible tarballs (#35623)
Bootstrap most of Spack dependencies using environments (#34029)
Split satisfies(..., strict=True/False) into two functions (#35681)
spack install: simplify behavior when inside environments (#35206)

Binary cache and stack updates

Major simplification of CI boilerplate in stacks (#34272, #36045)
Many improvements to our CI pipeline's reliability

Removals, Deprecations, and disablements

Module file generation is disabled by default; you'll need to enable it to use it (#37258)
Support for Python 2 was deprecated in v0.19.0 and has been removed. v0.20.0 only supports Python 3.6 and higher.
Deprecated target names are no longer recognized by Spack. Use generic names instead:
- graviton is now cortex_a72
- graviton2 is now neoverse_n1
- graviton3 is now neoverse_v1
blacklist and whitelist in module configuration were deprecated in v0.19.0 and are removed in this release. Use exclude and include instead.
The ignore= parameter of the extends() directive has been removed. It was not used by any builtin packages and is no longer needed to avoid conflicts in environment views (#35588).
Support for the old YAML buildcache format has been removed. It was deprecated in v0.19.0 (#34347).
spack find --bootstrap has been removed. It was deprecated in v0.19.0. Use spack --bootstrap find instead (#33964).
spack bootstrap trust and spack bootstrap untrust are now removed, having been deprecated in v0.19.0. Use spack bootstrap enable and spack bootstrap disable.
The --mirror-name, --mirror-url, and --directory options to buildcache and mirror commands were deprecated in v0.19.0 and have now been removed. They have been replaced by positional arguments (#37457).
Deprecate env: as top level environment key (#37424)
deprecate buildcache create --rel, buildcache install --allow-root (#37285)
Support for very old perl-like spec format strings (e.g., $_$@$%@+$+$=) has been removed (#37425). This was deprecated in in v0.15 (#10556).

Notable Bugfixes

bugfix: don't fetch package metadata for unknown concrete specs (#36990)
Improve package source code context display on error (#37655)
Relax environment manifest filename requirements and lockfile identification criteria (#37413)
installer.py: drop build edges of installed packages by default (#36707)
Bugfix: package requirements with git commits (#35057, #36347)
Package requirements: allow single specs in requirement lists (#36258)
conditional variant values: allow boolean (#33939)
spack uninstall: follow run/link edges on --dependents (#34058)

Spack community stats

7,179 total packages, 499 new since v0.19.0
- 329 new Python packages
- 31 new R packages
336 people contributed to this release
- 317 committers to packages
- 62 committers to core

v0.19.1 (2023-02-07)

Spack Bugfixes

buildcache create: make "file exists" less verbose (#35019)
spack mirror create: don't change paths to urls (#34992)
Improve error message for requirements (#33988)
uninstall: fix accidental cubic complexity (#34005)
scons: fix signature for install_args (#34481)
Fix combine_phase_logs text encoding issues (#34657)
Use a module-like object to propagate changes in the MRO, when setting build env (#34059)
PackageBase should not define builder legacy attributes (#33942)
Forward lookup of the "run_tests" attribute (#34531)
Bugfix for timers (#33917, #33900)
Fix path handling in prefix inspections (#35318)
Fix libtool filter for Fujitsu compilers (#34916)
Bug fix for duplicate rpath errors on macOS when creating build caches (#34375)
FileCache: delete the new cache file on exception (#34623)
Propagate exceptions from Spack python console (#34547)
Tests: Fix a bug/typo in a config_values.py fixture (#33886)
Various CI fixes (#33953, #34560, #34560, #34828)
Docs: remove monitors and analyzers, typos (#34358, #33926)
bump release version for tutorial command (#33859)

v0.19.0 (2022-11-11)

v0.19.0 is a major feature release.

Major features in this release

Package requirements

Spack's traditional package preferences are soft, but we've added hard requriements to packages.yaml and spack.yaml (#32528, #32369). Package requirements use the same syntax as specs:
```
packages:
  libfabric:
    require: "@1.13.2"
  mpich:
    require:
    - one_of: ["+cuda", "+rocm"]
```
More details in the docs.
Environment UI Improvements
- Fewer surprising modifications to spack.yaml (#33711):
  - spack install in an environment will no longer add to the specs: list; you'll need to either use spack add <spec> or spack install --add <spec>.
  - Similarly, spack uninstall will not remove from your environment's specs: list; you'll need to use spack remove or spack uninstall --remove.
  This will make it easier to manage an environment, as there is clear separation between the stack to be installed (spack.yaml/spack.lock) and which parts of it should be installed (spack install / spack uninstall).
- concretizer:unify:true is now the default mode for new environments (#31787)
  
  We see more users creating unify:true environments now. Users who need unify:false can add it to their environment to get the old behavior. This will concretize every spec in the environment independently.
- Include environment configuration from URLs (#29026, docs)
  
  You can now include configuration in your environment directly from a URL:
```
spack:
  include:
  - https://github.com/path/to/raw/config/compilers.yaml
```

Multiple Build Systems

An increasing number of packages in the ecosystem need the ability to support multiple build systems (#30738, docs), either across versions, across platforms, or within the same version of the software. This has been hard to support through multiple inheritance, as methods from different build system superclasses would conflict. package.py files can now define separate builder classes with installation logic for different build systems, e.g.:

class ArpackNg(CMakePackage, AutotoolsPackage):

    build_system(
        conditional("cmake", when="@0.64:"),
        conditional("autotools", when="@:0.63"),
        default="cmake",
    )

class CMakeBuilder(spack.build_systems.cmake.CMakeBuilder):
    def cmake_args(self):
        pass

class Autotoolsbuilder(spack.build_systems.autotools.AutotoolsBuilder):
    def configure_args(self):
        pass

Compiler and variant propagation

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.

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==-g: cflags will be propagated to dependencies
- package cflags=-g: cflags will NOT be propagated to dependencies
Syntax for non-boolan variants is similar to compiler flags. More in the docs for variants and compiler flags.

Enhancements to git version specifiers

v0.18.0 added the ability to use git commits as versions. You can now use the git. prefix to specify git tags or branches as versions. All of these are valid git versions in v0.19 (#31200):

foo@abcdef1234abcdef1234abcdef1234abcdef1234      # raw commit
foo@git.abcdef1234abcdef1234abcdef1234abcdef1234  # commit with git prefix
foo@git.develop                                   # the develop branch
foo@git.0.19                                      # use the 0.19 tag

v0.19 also gives you more control over how Spack interprets git versions, in case Spack cannot detect the version from the git repository. You can suffix a git version with =<version> to force Spack to concretize it as a particular version (#30998, #31914, #32257):
```
# use mybranch, but treat it as version 3.2 for version comparison
foo@git.mybranch=3.2

# use the given commit, but treat it as develop for version comparison
foo@git.abcdef1234abcdef1234abcdef1234abcdef1234=develop
```
More in the docs

Changes to Cray EX Support

Cray machines have historically had their own "platform" within Spack, because we needed to go through the module system to leverage compilers and MPI installations on these machines. The Cray EX programming environment now provides standalone craycc executables and proper mpicc wrappers, so Spack can treat EX machines like Linux with extra packages (#29392).

We expect this to greatly reduce bugs, as external packages and compilers can now be used by prefix instead of through modules. We will also no longer be subject to reproducibility issues when modules change from Cray PE release to release and from site to site. This also simplifies dealing with the underlying Linux OS on cray systems, as Spack will properly model the machine's OS as either SuSE or RHEL.
Improvements to tests and testing in CI
- spack ci generate --tests will generate a .gitlab-ci.yml file that not only does builds but also runs tests for built packages (#27877). Public GitHub pipelines now also run tests in CI.
- spack test run --explicit will only run tests for packages that are explicitly installed, instead of all packages.
Experimental binding link model

You can add a new option to config.yaml to make Spack embed absolute paths to needed shared libraries in ELF executables and shared libraries on Linux (#31948, docs):
```
config:
  shared_linking:
    type: rpath
    bind: true
```
This can improve launch time at scale for parallel applications, and it can make installations less susceptible to environment variables like LD_LIBRARY_PATH, even especially when dealing with external libraries that use RUNPATH. You can think of this as a faster, even higher-precedence version of RPATH.

Other new features of note

spack spec prints dependencies more legibly. Dependencies in the output now appear at the earliest level of indentation possible (#33406)
You can override package.py attributes like url, directly in packages.yaml (#33275, docs)
There are a number of new architecture-related format strings you can use in Spack configuration files to specify paths (#29810, docs)
Spack now supports bootstrapping Clingo on Windows (#33400)
There is now support for an RPATH-like library model on Windows (#31930)

Performance Improvements

Major performance improvements for installation from binary caches (#27610, #33628, #33636, #33608, #33590, #33496)
Test suite can now be parallelized using xdist (used in GitHub Actions) (#32361)
Reduce lock contention for parallel builds in environments (#31643)

New binary caches and stacks

We now build nearly all of E4S with oneapi in our buildcache (#31781, #31804, #31804, #31803, #31840, #31991, #32117, #32107, #32239)
Added 3 new machine learning-centric stacks to binary cache: x86_64_v3, CUDA, ROCm (#31592, #33463)

Removals and Deprecations

Support for Python 3.5 is dropped (#31908). Only Python 2.7 and 3.6+ are officially supported.
This is the last Spack release that will support Python 2 (#32615). Spack v0.19 will emit a deprecation warning if you run it with Python 2, and Python 2 support will soon be removed from the develop branch.
LD_LIBRARY_PATH is no longer set by default by spack load or module loads.

Setting LD_LIBRARY_PATH in Spack environments/modules can cause binaries from outside of Spack to crash, and Spack's own builds use RPATH and do not need LD_LIBRARY_PATH set in order to run. If you still want the old behavior, you can run these commands to configure Spack to set LD_LIBRARY_PATH:
```
spack config add modules:prefix_inspections:lib64:[LD_LIBRARY_PATH]
spack config add modules:prefix_inspections:lib:[LD_LIBRARY_PATH]
```
The spack:concretization:[together|separately] has been removed after being deprecated in v0.18. Use concretizer:unify:[true|false].
config:module_roots is no longer supported after being deprecated in v0.18. Use configuration in module sets instead (#28659, docs).
spack activate and spack deactivate are no longer supported, having been deprecated in v0.18. Use an environment with a view instead of activating/deactivating (docs).
The old YAML format for buildcaches is now deprecated (#33707). If you are using an old buildcache with YAML metadata you will need to regenerate it with JSON metadata.
spack bootstrap trust and spack bootstrap untrust are deprecated in favor of spack bootstrap enable and spack bootstrap disable and will be removed in v0.20. (#33600)
The graviton2 architecture has been renamed to neoverse_n1, and graviton3 is now neoverse_v1. Buildcaches using the old architecture names will need to be rebuilt.
The terms blacklist and whitelist have been replaced with include and exclude in all configuration files (#31569). You can use spack config update to automatically fix your configuration files.

Notable Bugfixes

Permission setting on installation now handles effective uid properly (#19980)
buildable:true for an MPI implementation now overrides buildable:false for mpi (#18269)
Improved error messages when attempting to use an unconfigured compiler (#32084)
Do not punish explicitly requested compiler mismatches in the solver (#30074)
spack stage: add missing --fresh and --reuse (#31626)
Fixes for adding build system executables like cmake to package scope (#31739)
Bugfix for binary relocation with aliased strings produced by newer binutils (#32253)

Spack community stats

6,751 total packages, 335 new since v0.18.0
- 141 new Python packages
- 89 new R packages
303 people contributed to this release
- 287 committers to packages
- 57 committers to core

v0.18.1 (2022-07-19)

Spack Bugfixes

Fix several bugs related to bootstrapping (#30834,#31042,#31180)
Fix a regression that was causing spec hashes to differ between Python 2 and Python 3 (#31092)
Fixed compiler flags for oneAPI and DPC++ (#30856)
Fixed several issues related to concretization (#31142,#31153,#31170,#31226)
Improved support for Cray manifest file and spack external find (#31144,#31201,#31173,#31186)
Assign a version to openSUSE Tumbleweed according to the GLIBC version in the system (#19895)
Improved Dockerfile generation for spack containerize (#29741,#31321)
Fixed a few bugs related to concurrent execution of commands (#31509,#31493,#31477)

Package updates

WarpX: add v22.06, fixed libs property (#30866,#31102)
openPMD: add v0.14.5, update recipe for @develop (#29484,#31023)

v0.18.0 (2022-05-28)

v0.18.0 is a major feature release.

Major features in this release

Concretizer now reuses by default

spack install --reuse was introduced in v0.17.0, and --reuse is now the default concretization mode. Spack will try hard to resolve dependencies using installed packages or binaries (#30396).

To avoid reuse and to use the latest package configurations, (the old default), you can use spack install --fresh, or add configuration like this to your environment or concretizer.yaml:
```
concretizer:
    reuse: false
```
Finer-grained hashes

Spack hashes now include link, run, and build dependencies, as well as a canonical hash of package recipes. Previously, hashes only included link and run dependencies (though build dependencies were stored by environments). We coarsened the hash to reduce churn in user installations, but the new default concretizer behavior mitigates this concern and gets us reuse and provenance. You will be able to see the build dependencies of new installations with spack find. Old installations will not change and their hashes will not be affected. (#28156, #28504, #30717, #30861)
Improved error messages

Error handling with the new concretizer is now done with optimization criteria rather than with unsatisfiable cores, and Spack reports many more details about conflicting constraints. (#30669)
Unify environments when possible

Environments have thus far supported concretization: together or concretization: separately. These have been replaced by a new preference in concretizer.yaml:
```
concretizer:
    unify: [true|false|when_possible]
```
concretizer:unify:when_possible will try to resolve a fully unified environment, but if it cannot, it will create multiple configurations of some packages where it has to. For large environments that previously had to be concretized separately, this can result in a huge speedup (40-50x). (#28941)
Automatically find externals on Cray machines

Spack can now automatically discover installed packages in the Cray Programming Environment by running spack external find (or spack external read-cray-manifest to only query the PE). Packages from the PE (e.g., cray-mpich are added to the database with full dependency information, and compilers from the PE are added to compilers.yaml. Available with the June 2022 release of the Cray Programming Environment. (#24894, #30428)
New binary format and hardened signing

Spack now has an updated binary format, with improvements for security. The new format has a detached signature file, and Spack verifies the signature before untarring or decompressing the binary package. The previous format embedded the signature in a tar file, which required the client to run tar before verifying (#30750). Spack can still install from build caches using the old format, but we encourage users to switch to the new format going forward.

Production GitLab pipelines have been hardened to securely sign binaries. There is now a separate signing stage so that signing keys are never exposed to build system code, and signing keys are ephemeral and only live as long as the signing pipeline stage. (#30753)
Bootstrap mirror generation

The spack bootstrap mirror command can automatically create a mirror for bootstrapping the concretizer and other needed dependencies in an air-gapped environment. (#28556)
Nascent Windows support

Spack now has initial support for Windows. Spack core has been refactored to run in the Windows environment, and a small number of packages can now build for Windows. More details are in the documentation (#27021, #28385, many more)
Makefile generation

spack env depfile can be used to generate a Makefile from an environment, which can be used to build packages the environment in parallel on a single node. e.g.:
```
spack -e myenv env depfile > Makefile
make
```
Spack propagates gmake jobserver information to builds so that their jobs can share cores. (#30039, #30254, #30302, #30526)
New variant features

In addition to being conditional themselves, variants can now have conditional values that are only possible for certain configurations of a package. (#29530)

Variants can be declared "sticky", which prevents them from being enabled or disabled by the concretizer. Sticky variants must be set explicitly by users on the command line or in packages.yaml. (#28630)

Allow conditional possible values in variants
Add a "sticky" property to variants

Other new features of note

Environment views can optionally link only run dependencies with link:run (#29336)
spack external find --all finds library-only packages in addition to build dependencies (#28005)
Customizable config:license_dir option (#30135)
spack external find --path PATH takes a custom search path (#30479)
spack spec has a new --format argument like spack find (#27908)
spack concretize --quiet skips printing concretized specs (#30272)
spack info now has cleaner output and displays test info (#22097)
Package-level submodule option for git commit versions (#30085, #30037)
Using /hash syntax to refer to concrete specs in an environment now works even if /hash is not installed. (#30276)

Major internal refactors

full hash (see above)
new develop versioning scheme 0.19.0-dev0
Allow for multiple dependencies/dependents from the same package (#28673)
Splice differing virtual packages (#27919)

Performance Improvements

Concretization of large environments with unify: when_possible is much faster than concretizing separately (#28941, see above)
Single-pass view generation algorithm is 2.6x faster (#29443)

Archspec improvements

oneapi and dpcpp flag support (#30783)
better support for M1 and a64fx (#30683)

Removals and Deprecations

Spack no longer supports Python 2.6 (#27256)
Removed deprecated --run-tests option of spack install; use spack test (#30461)
Removed deprecated spack flake8; use spack style (#27290)
Deprecate spack:concretization config option; use concretizer:unify (#30038)
Deprecate top-level module configuration; use module sets (#28659)
spack activate and spack deactivate are deprecated in favor of environments; will be removed in 0.19.0 (#29430; see also link:run in #29336 above)

Notable Bugfixes

Fix bug that broke locks with many parallel builds (#27846)
Many bugfixes and consistency improvements for the new concretizer and --reuse (#30357, #30092, #29835, #29933, #28605, #29694, #28848)

Packages

CMakePackage uses CMAKE_INSTALL_RPATH_USE_LINK_PATH (#29703)
Refactored lua support: lua-lang virtual supports both lua and luajit via new LuaPackage build system(#28854)
PythonPackage: now installs packages with pip (#27798)
Python: improve site_packages_dir handling (#28346)
Extends: support spec, not just package name (#27754)
find_libraries: search for both .so and .dylib on macOS (#28924)
Use stable URLs and ?full_index=1 for all github patches (#29239)

Spack community stats

6,416 total packages, 458 new since v0.17.0
- 219 new Python packages
- 60 new R packages
377 people contributed to this release
- 337 committers to packages
- 85 committers to core

v0.17.3 (2022-07-14)

Spack bugfixes

Fix missing chgrp on symlinks in package installations (#30743)
Allow having non-existing upstreams (#30744, #30746)
Fix spack stage with custom paths (#30448)
Fix failing call for spack buildcache save-specfile (#30637)
Fix globbing in compiler wrapper (#30699)

v0.17.2 (2022-04-13)

Spack bugfixes

Fix --reuse with upstreams set in an environment (#29680)
config add: fix parsing of validator error to infer type from oneOf (#29475)
Fix spack -C command_line_scope used in conjunction with other flags (#28418)
Use Spec.constrain to construct spec lists for stacks (#28783)
Fix bug occurring when searching for inherited patches in packages (#29574)
Fixed a few bugs when manipulating symlinks (#28318, #29515, #29636)
Fixed a few minor bugs affecting command prompt, terminal title and argument completion (#28279, #28278, #28939, #29405, #29070, #29402)
Fixed a few bugs affecting the spack ci command (#29518, #29419)
Fix handling of Intel compiler environment (#29439)
Fix a few edge cases when reindexing the DB (#28764)
Remove "Known issues" from documentation (#29664)
Other miscellaneous bugfixes (0b72e070583fc5bcd016f5adc8a84c99f2b7805f, #28403, #29261)

v0.17.1 (2021-12-23)

Spack Bugfixes

Allow locks to work under high contention (#27846)
Improve errors messages from clingo (#27707 #27970)
Respect package permissions for sbang (#25764)
Fix --enable-locks behavior (#24675)
Fix log-format reporter ignoring install errors (#25961)
Fix overloaded argparse keys (#27379)
Allow style commands to run with targets other than "develop" (#27472)
Log lock messages to debug level, instead of verbose level (#27408)
Handle invalid unicode while logging (#21447)
spack audit: fix API calls to variants (#27713)
Provide meaningful message for empty environment installs (#28031)
Added opensuse leap containers to spack containerize (#27837)
Revert "patches: make re-applied patches idempotent" (#27625)
MANPATH can use system defaults (#21682)
Add "setdefault" subcommand to spack module tcl (#14686)
Regenerate views when specs already installed (#28113)

Package bugfixes

Fix external package detection for OpenMPI (#27255)
Update the UPC++ package to 2021.9.0 (#26996)
Added py-vermin v1.3.2 (#28072)

v0.17.0 (2021-11-05)

v0.17.0 is a major feature release.

Major features in this release

New concretizer is now default The new concretizer introduced as an experimental feature in v0.16.0 is now the default (#25502). The new concretizer is based on the clingo logic programming system, and it enables us to do much higher quality and faster dependency solving The old concretizer is still available via the concretizer: original setting, but it is deprecated and will be removed in v0.18.0.
Binary Bootstrapping To make it easier to use the new concretizer and binary packages, Spack now bootstraps clingo and GnuPG from public binaries. If it is not able to bootstrap them from binaries, it installs them from source code. With these changes, you should still be able to clone Spack and start using it almost immediately. (#21446, #22354, #22489, #22606, #22720, #22720, #23677, #23946, #24003, #25138, #25607, #25964, #26029, #26399, #26599).
Reuse existing packages (experimental) The most wanted feature from our 2020 user survey and the most wanted Spack feature of all time (#25310). spack install, spack spec, and spack concretize now have a --reuse option, which causes Spack to minimize the number of rebuilds it does. The --reuse option will try to find existing installations and binary packages locally and in registered mirrors, and will prefer to use them over building new versions. This will allow users to build from source far less than in prior versions of Spack. This feature will continue to be improved, with configuration options and better CLI expected in v0.17.1. It will become the default concretization mode in v0.18.0.
Better error messages We have improved the error messages generated by the new concretizer by using unsatisfiable cores. Spack will now print a summary of the types of constraints that were violated to make a spec unsatisfiable (#26719).
Conditional variants Variants can now have a when="<spec>" clause, allowing them to be conditional based on the version or other attributes of a package (#24858).
Git commit versions In an environment and on the command-line, you can now provide a full, 40-character git commit as a version for any package with a top-level git URL. e.g., spack install hdf5@45bb27f58240a8da7ebb4efc821a1a964d7712a8. Spack will compare the commit to tags in the git repository to understand what versions it is ahead of or behind.
Override local config and cache directories You can now set SPACK_DISABLE_LOCAL_CONFIG to disable the ~/.spack and /etc/spack configuration scopes. SPACK_USER_CACHE_PATH allows you to move caches out of ~/.spack, as well (#27022, #26735). This addresses common problems where users could not isolate CI environments from local configuration.
Improvements to Spack Containerize For added reproducibility, you can now pin the Spack version used by spack containerize (#21910). The container build will only build with the Spack version pinned at build recipe creation instead of the latest Spack version.
New commands for dealing with tags The spack tags command allows you to list tags on packages (#26136), and you can list tests and filter tags with spack test list (#26842).

Other new features of note

Copy and relocate environment views as stand-alone installations (#24832)
spack diff command can diff two installed specs (#22283, #25169)
spack -c <config> can set one-off config parameters on CLI (#22251)
spack load --list is an alias for spack find --loaded (#27184)
spack gpg can export private key with --secret (#22557)
spack style automatically bootstraps dependencies (#24819)
spack style --fix automatically invokes isort (#24071)
build dependencies can be installed from build caches with --include-build-deps (#19955)
spack audit command for checking package constraints (#23053)
Spack can now fetch from CVS repositories (yep, really) (#23212)
spack monitor lets you upload analysis about installations to a spack monitor server (#23804, #24321, #23777, #25928))
spack python --path shows which python Spack is using (#22006)
spack env activate --temp can create temporary environments (#25388)
--preferred and --latest options for spack checksum (#25830)
cc is now pure posix and runs on Alpine (#26259)
SPACK_PYTHON environment variable sets which python spack uses (#21222)
SPACK_SKIP_MODULES lets you source setup-env.sh faster if you don't need modules (#24545)

Major internal refactors

spec.yaml files are now spec.json, yielding a large speed improvement (#22845)
Splicing allows Spack specs to store mixed build provenance (#20262)
More extensive hooks API for installations (#21930)
New internal API for getting the active environment (#25439)

Performance Improvements

Parallelize separate concretization in environments; Previously 55 min E4S solve now takes 2.5 min (#26264)
Drastically improve YamlFilesystemView file removal performance via batching (#24355)
Speed up spec comparison (#21618)
Speed up environment activation (#25633)

Archspec improvements

support for new generic x86_64_v2, x86_64_v3, x86_64_v4 targets (see archspec#31)
spack arch --generic lets you get the best generic architecture for your node (#27061)
added support for aocc (#20124), arm compiler on graviton2 (#24904) and on a64fx (#24524),

Infrastructure, buildcaches, and services

Add support for GCS Bucket Mirrors (#26382)
Add spackbot to help package maintainers with notifications. See spack.github.io/spackbot
Reproducible pipeline builds with spack ci rebuild (#22887)
Removed redundant concretizations from GitLab pipeline generation (#26622)
Spack CI no longer generates jobs for unbuilt specs (#20435)
Every pull request pipeline has its own buildcache (#25529)
--no-add installs only specified specs and only if already present in… (#22657)
Add environment-aware spack buildcache sync command (#25470)
Binary cache installation speedups and improvements (#19690, #20768)

Deprecations and Removals

spack setup was deprecated in v0.16.0, and has now been removed. Use spack develop and spack dev-build.
Remove unused --dependencies flag from spack load (#25731)
Remove stubs for spack module [refresh|find|rm|loads], all of which were deprecated in 2018.

Notable Bugfixes

Deactivate previous env before activating new one (#25409)
Many fixes to error codes from spack install (#21319, #27012, #25314)
config add: infer type based on JSON schema validation errors (#27035)
spack config edit now works even if spack.yaml is broken (#24689)

Packages

Allow non-empty version ranges like 1.1.0:1.1 (#26402)
Remove .99's from many version ranges (#26422)
Python: use platform-specific site packages dir (#25998)
CachedCMakePackage for using *.cmake initial config files (#19316)
lua-lang allows swapping lua and luajit (#22492)
Better support for ld.gold and ld.lld (#25626)
build times are now stored as metadata in $prefix/.spack (#21179)
post-install tests can be reused in smoke tests (#20298)
Packages can use pypi attribute to infer homepage/url/list_url (#17587)
Use gnuconfig package for config.guess file replacement (#26035)
patches: make re-applied patches idempotent (#26784)

Spack community stats

5969 total packages, 920 new since v0.16.0
- 358 new Python packages, 175 new R packages
513 people contributed to this release
- 490 committers to packages
- 105 committers to core
Lots of GPU updates:
- ~77 CUDA-related commits
- ~66 AMD-related updates
- ~27 OneAPI-related commits
- 30 commits from AMD toolchain support
spack test usage in packages is increasing
- 1669 packages with tests (mostly generic python tests)
- 93 packages with their own tests

v0.16.3 (2021-09-21)

clang/llvm: fix version detection (#19978)
Fix use of quotes in Python build system (#22279)
Cray: fix extracting paths from module files (#23472)
Use AWS CloudFront for source mirror (#23978)
Ensure all roots of an installed environment are marked explicit in db (#24277)
Fix fetching for Python 3.8 and 3.9 (#24686)
locks: only open lockfiles once instead of for every lock held (#24794)
Remove the EOL centos:6 docker image

v0.16.2 (2021-05-22)

Major performance improvement for spack load and other commands. (#23661)
spack fetch is now environment-aware. (#19166)
Numerous fixes for the new, clingo-based concretizer. (#23016, #23307, #23090, #22896, #22534, #20644, #20537, #21148)
Supoprt for automatically bootstrapping clingo from source. (#20652, #20657 #21364, #21446, #21913, #22354, #22444, #22460, #22489, #22610, #22631)
Python 3.10 support: collections.abc (#20441)
Fix import issues by using __import__ instead of Spack package importe. (#23288, #23290)
Bugfixes and --source-dir argument for spack location. (#22755, #22348, #22321)
Better support for externals in shared prefixes. (#22653)
spack build-env now prefers specs defined in the active environment. (#21642)
Remove erroneous warnings about quotes in from_sourcing_files. (#22767)
Fix clearing cache of InternalConfigScope. (#22609)
Bugfix for active when pkg is already active error. (#22587)
Make SingleFileScope able to repopulate the cache after clearing it. (#22559)
Channelflow: Fix the package. (#22483)
More descriptive error message for bugs in package.py (#21811)
Use package-supplied autogen.sh. (#20319)
Respect -k/verify-ssl-false in _existing_url method. (#21864)

v0.16.1 (2021-02-22)

This minor release includes a new feature and associated fixes:

intel-oneapi support through new packages (#20411, #20686, #20693, #20717, #20732, #20808, #21377, #21448)

This release also contains bug fixes/enhancements for:

HIP/ROCm support (#19715, #20095)
concretization (#19988, #20020, #20082, #20086, #20099, #20102, #20128, #20182, #20193, #20194, #20196, #20203, #20247, #20259, #20307, #20362, #20383, #20423, #20473, #20506, #20507, #20604, #20638, #20649, #20677, #20680, #20790)
environment install reporting fix (#20004)
avoid import in ABI compatibility info (#20236)
restore ability of dev-build to skip patches (#20351)
spack find -d spec grouping (#20028)
spack smoke test support (#19987, #20298)
macOS fixes (#20038, #21662)
abstract spec comparisons (#20341)
continuous integration (#17563)
performance improvements for binary relocation (#19690, #20768)
additional sanity checks for variants in builtin packages (#20373)
do not pollute auto-generated configuration files with empty lists or dicts (#20526)

plus assorted documentation (#20021, #20174) and package bug fixes/enhancements (#19617, #19933, #19986, #20006, #20097, #20198, #20794, #20906, #21411).

v0.16.0 (2020-11-18)

v0.16.0 is a major feature release.

Major features in this release

New concretizer (experimental) Our new backtracking concretizer is now in Spack as an experimental feature. You will need to install clingo@master+python and set concretizer: clingo in config.yaml to use it. The original concretizer is not exhaustive and is not guaranteed to find a solution if one exists. We encourage you to use the new concretizer and to report any bugs you find with it. We anticipate making the new concretizer the default and including all required dependencies for it in Spack v0.17. For more details, see #19501.
spack test (experimental) Users can add test() methods to their packages to run smoke tests on installations with the new spack test command (the old spack test is now spack unit-test). spack test is environment-aware, so you can spack install an environment and spack test run smoke tests on all of its packages. Historical test logs can be perused with spack test results. Generic smoke tests for MPI implementations, C, C++, and Fortran compilers as well as specific smoke tests for 18 packages. This is marked experimental because the test API (self.run_test()) is likely to be change, but we encourage users to upstream tests, and we will maintain and refactor any that are added to mainline packages (#15702).
spack develop New spack develop command allows you to develop several packages at once within a Spack environment. Running spack develop foo@v1 and spack develop bar@v2 will check out specific versions of foo and bar into subdirectories, which you can then build incrementally with spack install (#15256).
More parallelism Spack previously installed the dependencies of a single spec in parallel. Entire environments can now be installed in parallel, greatly accelerating builds of large environments. get parallelism from individual specs. Spack now parallelizes entire environment builds (#18131).
Customizable base images for spack containerize spack containerize previously only output a Dockerfile based on ubuntu. You may now specify any base image of your choosing (#15028).
more external finding spack external find was added in v0.15, but only cmake had support. spack external find can now find bison, cuda, findutils, flex, git, lustre m4, mpich, mvapich2, ncurses, openmpi, perl, spectrum-mpi, tar, and texinfo on your system and add them automatically to packages.yaml.
Support aocc, nvhpc, and oneapi compilers We are aggressively pursuing support for the newest vendor compilers, especially those for the U.S. exascale and pre-exascale systems. Compiler classes and auto-detection for aocc, nvhpc, oneapi are now in Spack (#19345, #19294, #19330).

Additional new features of note

New spack mark command can be used to designate packages as explicitly installed, so that spack gc will not garbage-collect them (#16662).
install_tree can be customized with Spack's projection format (#18341)
sbang now lives in the install_tree so that all users can access it (#11598)
csh and tcsh users no longer need to set SPACK_ROOT before sourcing setup-env.csh (#18225)
Spec syntax now supports variant=* syntax for finding any package that has a particular variant (#19381).
Spack respects SPACK_GNUPGHOME variable for custom GPG directories (#17139)
Spack now recognizes Graviton chips

Major refactors

Use spawn instead of fork on Python >= 3.8 on macOS (#18205)
Use indexes for public build caches (#19101, #19117, #19132, #19141, #19209)
sbang is an external package now (https://github.com/spack/sbang, #19582)
archspec is an external package now (https://github.com/archspec/archspec, #19600)

Deprecations and Removals

spack bootstrap was deprecated in v0.14.0, and has now been removed.
spack setup is deprecated as of v0.16.0.
What was spack test is now called spack unit-test. spack test is now the smoke testing feature in (2) above.

Bugfixes

Some of the most notable bugfixes in this release include:

Better warning messages for deprecated syntax in packages.yaml (#18013)
buildcache list --allarch now works properly (#17827)
Many fixes and tests for buildcaches and binary relcoation (#15687, *#17455, #17418, #17455, #15687, #18110)

Package Improvements

Spack now has 5050 total packages, 720 of which were added since v0.15.

ROCm packages (hip, aomp, more) added by AMD (#19957, #19832, others)
Many improvements for ARM support
llvm-flang, flang, and f18 removed, as llvm has real flang support since Flang was merged to LLVM mainline
Emerging support for spack external find and spack test in packages.

Infrastructure

Major infrastructure improvements to pipelines on gitlab.spack.io
Support for testing PRs from forks (#19248) is being enabled for all forks to enable rolling, up-to-date binary builds on develop

v0.15.4 (2020-08-12)

This release contains one feature addition:

Users can set SPACK_GNUPGHOME to override Spack's GPG path (#17139)

Several bugfixes for CUDA, binary packaging, and spack -V:

CUDA package's .libs method searches for libcudart instead of libcuda (#18000)
Don't set CUDAHOSTCXX in environments that contain CUDA (#17826)
buildcache create: NoOverwriteException is a warning, not an error (#17832)
Fix spack buildcache list --allarch (#17884)
spack -V works with releases/latest tag and shallow clones (#17884)

And fixes for GitHub Actions and tests to ensure that CI passes on the release branch (#15687, #17279, #17328, #17377, #17732).

v0.15.3 (2020-07-28)

This release contains the following bugfixes:

Fix handling of relative view paths (#17721)
Fixes for binary relocation (#17418, #17455)
Fix redundant printing of error messages in build environment (#17709)

It also adds a support script for Spack tutorials:

Add a tutorial setup script to share/spack (#17705, #17722)

v0.15.2 (2020-07-23)

This minor release includes two new features:

Spack install verbosity is decreased, and more debug levels are added (#17546)
The $spack/share/spack/keys directory contains public keys that may be optionally trusted for public binary mirrors (#17684)

This release also includes several important fixes:

MPICC and related variables are now cleand in the build environment (#17450)
LLVM flang only builds CUDA offload components when +cuda (#17466)
CI pipelines no longer upload user environments that can contain secrets to the internet (#17545)
CI pipelines add bootstrapped compilers to the compiler config (#17536)
spack buildcache list does not exit on first failure and lists later mirrors (#17565)
Apple's "gcc" executable that is an apple-clang compiler does not generate a gcc compiler config (#17589)
Mixed compiler toolchains are merged more naturally across different compiler suffixes (#17590)
Cray Shasta platforms detect the OS properly (#17467)
Additional more minor fixes.

v0.15.1 (2020-07-10)

This minor release includes several important fixes:

Fix shell support on Cray (#17386)
Fix use of externals installed with other Spack instances (#16954)
Fix gcc+binutils build (#9024)
Fixes for usage of intel-mpi (#17378 and #17382)
Fixes to Autotools config.guess detection (#17333 and #17356)
Update spack install message to prompt user when an environment is not explicitly activated (#17454)

This release also adds a mirror for all sources that are fetched in Spack (#17077). It is expected to be useful when the official website for a Spack package is unavailable.

v0.15.0 (2020-06-28)

v0.15.0 is a major feature release.

Major Features in this release

Cray support Spack will now work properly on Cray "Cluster" systems (non XC systems) and after a module purge command on Cray systems. See #12989
Virtual package configuration Virtual packages are allowed in packages.yaml configuration. This allows users to specify a virtual package as non-buildable without needing to specify for each implementation. See #14934
New config subcommands This release adds spack config add and spack config remove commands to add to and remove from yaml configuration files from the CLI. See #13920
Environment activation Anonymous environments are no longer automatically activated in the current working directory. To activate an environment from a spack.yaml file in the current directory, use the spack env activate . command. This removes a concern that users were too easily polluting their anonymous environments with accidental installations. See #17258
Apple clang compiler The clang compiler and the apple-clang compiler are now separate compilers in Spack. This allows Spack to improve support for the apple-clang compiler. See #17110
Finding external packages Spack packages can now support an API for finding external installations. This allows the spack external find command to automatically add installations of those packages to the user's configuration. See #15158

Additional new features of note

support for using Spack with the fish shell (#9279)
spack load --first option to load first match (instead of prompting user) (#15622)
support the Cray cce compiler both new and classic versions (#17256, #12989)
spack dev-build command:
- supports stopping before a specified phase (#14699)
- supports automatically launching a shell in the build environment (#14887)
spack install --fail-fast allows builds to fail at the first error (rather than best-effort) (#15295)
environments: SpecList references can be dereferenced as compiler or dependency constraints (#15245)
spack view command: new support for a copy/relocate view type (#16480)
ci pipelines: see documentation for several improvements
spack mirror -a command now supports excluding packages (#14154)
spack buildcache create is now environment-aware (#16580)
module generation: more flexible format for specifying naming schemes (#16629)
lmod module generation: packages can be configured as core specs for lmod hierarchy (#16517)

Deprecations and Removals

The following commands were deprecated in v0.13.0, and have now been removed:

spack configure
spack build
spack diy

The following commands were deprecated in v0.14.0, and will be removed in the next major release:

spack bootstrap

Bugfixes

Some of the most notable bugfixes in this release include:

Spack environments can now contain the string -h (#15429)
The spack install gracefully handles being backgrounded (#15723, #14682)
Spack uses -isystem instead of -I in cases that the underlying build system does as well (#16077)
Spack no longer prints any specs that cannot be safely copied into a Spack command (#16462)
Incomplete Spack environments containing python no longer cause problems (#16473)
Several improvements to binary package relocation

Package Improvements

The Spack project is constantly engaged in routine maintenance, bugfixes, and improvements for the package ecosystem. Of particular note in this release are the following:

Spack now contains 4339 packages. There are 430 newly supported packages in v0.15.0
GCC now builds properly on ARM architectures (#17280)
Python: patched to support compiling mixed C/C++ python modules through distutils (#16856)
improvements to pytorch and py-tensorflow packages
improvements to major MPI implementations: mvapich2, mpich, openmpi, and others

Spack Project Management:

Much of the Spack CI infrastructure has moved from Travis to GitHub Actions (#16610, #14220, #16345)
All merges to the develop branch run E4S CI pipeline (#16338)
New spack debug report command makes reporting bugs easier (#15834)

v0.14.2 (2020-04-15)

This is a minor release on the 0.14 series. It includes performance improvements and bug fixes:

Improvements to how spack install handles foreground/background (#15723)
Major performance improvements for reading the package DB (#14693, #15777)
No longer check for the old index.yaml database file (#15298)
Properly activate environments with '-h' in the name (#15429)
External packages have correct .prefix in environments/views (#15475)
Improvements to computing env modifications from sourcing files (#15791)
Bugfix on Cray machines when getting TERM env variable (#15630)
Avoid adding spurious LMOD env vars to Intel modules (#15778)
Don't output [+] for mock installs run during tests (#15609)

v0.14.1 (2020-03-20)

This is a bugfix release on top of v0.14.0. Specific fixes include:

several bugfixes for parallel installation (#15339, #15341, #15220, #15197)
spack load now works with packages that have been renamed (#14348)
bugfix for suite-sparse installation (#15326)
deduplicate identical suffixes added to module names (#14920)
fix issues with configure_args during module refresh (#11084)
increased test coverage and test fixes (#15237, #15354, #15346)
remove some unused code (#15431)

v0.14.0 (2020-02-23)

v0.14.0 is a major feature release, with 3 highlighted features:

Distributed builds. Multiple Spack instances will now coordinate properly with each other through locks. This works on a single node (where you've called spack several times) or across multiple nodes with a shared filesystem. For example, with SLURM, you could build trilinos and its dependencies on 2 24-core nodes, with 3 Spack instances per node and 8 build jobs per instance, with srun -N 2 -n 6 spack install -j 8 trilinos. This requires a filesystem with locking enabled, but not MPI or any other library for parallelism.
Build pipelines. You can also build in parallel through Gitlab CI. Simply create a Spack environment and push it to Gitlab to build on Gitlab runners. Pipeline support is now integrated into a single spack ci command, so setting it up is easier than ever. See the Pipelines section in the docs.
Container builds. The new spack containerize command allows you to create a Docker or Singularity recipe from any Spack environment. There are options to customize the build if you need them. See the Container Images section in the docs.

In addition, there are several other new commands, many bugfixes and improvements, and spack load no longer requires modules, so you can use it the same way on your laptop or on your supercomputer.

Spack grew by over 300 packages since our last release in November 2019, and the project grew to over 500 contributors. Thanks to all of you for making yet another great release possible. Detailed notes below.

Major new core features

Distributed builds: spack instances coordinate and build in parallel (#13100)
New spack ci command to manage CI pipelines (#12854)
Generate container recipes from environments: spack containerize (#14202)
spack load now works without using modules (#14062, #14628)
Garbage collect old/unused installations with spack gc (#13534)
Configuration files all set environment modifications the same way (#14372, docs)
spack commands --format=bash auto-generates completion (#14393, #14607)
Packages can specify alternate fetch URLs in case one fails (#13881)

Improvements

Improved locking for concurrency with environments (#14676, #14621, #14692)
spack test sends args to pytest, supports better listing (#14319)
Better support for aarch64 and cascadelake microarch (#13825, #13780, #13820)
Archspec is now a separate library (see https://github.com/archspec/archspec)
Many improvements to the spack buildcache command (#14237, #14346, #14466, #14467, #14639, #14642, #14659, #14696, #14698, #14714, #14732, #14929, #15003, #15086, #15134)

Selected Bugfixes

Compilers now require an exact match on version (#8735, #14730, #14752)
Bugfix for patches that specified specific versions (#13989)
spack find -p now works in environments (#10019, #13972)
Dependency queries work correctly in spack find (#14757)
Bugfixes for locking upstream Spack instances chains (#13364)
Fixes for PowerPC clang optimization flags (#14196)
Fix for issue with compilers and specific microarchitectures (#13733, #14798)

New commands and options

spack ci (#12854)
spack containerize (#14202)
spack gc (#13534)
spack load accepts --only package, --only dependencies (#14062, #14628)
spack commands --format=bash (#14393)
spack commands --update-completion (#14607)
spack install --with-cache has new option: --no-check-signature (#11107)
spack test now has --list, --list-long, and --list-names (#14319)
spack install --help-cdash moves CDash help out of the main help (#13704)

Deprecations

spack release-jobs has been rolled into spack ci
spack bootstrap will be removed in a future version, as it is no longer needed to set up modules (see spack load improvements above)

Documentation

New section on building container images with Spack (see docs)
New section on using spack ci command to build pipelines (see docs)
Document how to add conditional dependencies (#14694)
Document how to use Spack to replace Homebrew/Conda (#13083, see docs)

Important package changes

3,908 total packages (345 added since 0.13.0)
Added first cut at a TensorFlow package (#13112)
We now build R without "recommended" packages, manage them w/Spack (#12015)
Elpa and OpenBLAS now leverage microarchitecture support (#13655, #14380)
Fix octave compiler wrapper usage (#14726)
Enforce that packages in builtin aren't missing dependencies (#13949)

v0.13.4 (2020-02-07)

This release contains several bugfixes:

bugfixes for invoking python in various environments (#14349, #14496, #14569)
brought tab completion up to date (#14392)
bugfix for removing extensions from views in order (#12961)
bugfix for nondeterministic hashing for specs with externals (#14390)

v0.13.3 (2019-12-23)

This release contains more major performance improvements for Spack environments, as well as bugfixes for mirrors and a python issue with RHEL8.

mirror bugfixes: symlinks, duplicate patches, and exception handling (#13789)
don't try to fetch BundlePackages (#13908)
avoid re-fetching patches already added to a mirror (#13908)
avoid re-fetching already added patches (#13908)
avoid re-fetching already added patches (#13908)
allow repeated invocations of spack mirror create on the same dir (#13908)
bugfix for RHEL8 when python is unavailable (#14252)
improve concretization performance in environments (#14190)
improve installation performance in environments (#14263)

v0.13.2 (2019-12-04)

This release contains major performance improvements for Spack environments, as well as some bugfixes and minor changes.

allow missing modules if they are blacklisted (#13540)
speed up environment activation (#13557)
mirror path works for unknown versions (#13626)
environments: don't try to modify run-env if a spec is not installed (#13589)
use semicolons instead of newlines in module/python command (#13904)
verify.py: os.path.exists exception handling (#13656)
Document use of the maintainers field (#13479)
bugfix with config caching (#13755)
hwloc: added 'master' version pointing at the HEAD of the master branch (#13734)
config option to allow gpg warning suppression (#13744)
fix for relative symlinks when relocating binary packages (#13727)
allow binary relocation of strings in relative binaries (#13724)

v0.13.1 (2019-11-05)

This is a bugfix release on top of v0.13.0. Specific fixes include:

spack find now displays variants and other spec constraints
bugfix: uninstall should find concrete specs by DAG hash (#13598)
environments: make shell modifications partially unconditional (#13523)
binary distribution: relocate text files properly in relative binaries (#13578)
bugfix: fetch prefers to fetch local mirrors over remote resources (#13545)
environments: only write when necessary (#13546)
bugfix: spack.util.url.join() now handles absolute paths correctly (#13488)
sbang: use utf-8 for encoding when patching (#13490)
Specs with quoted flags containing spaces are parsed correctly (#13521)
targets: print a warning message before downgrading (#13513)
Travis CI: Test Python 3.8 (#13347)
Documentation: Database.query methods share docstrings (#13515)
cuda: fix conflict statements for x86-64 targets (#13472)
cpu: fix clang flags for generic x86_64 (#13491)
syaml_int type should use int.repr rather than str.repr (#13487)
elpa: prefer 2016.05.004 until sse/avx/avx2 issues are resolved (#13530)
trilinos: temporarily constrain netcdf@:4.7.1 (#13526)

v0.13.0 (2019-10-25)

v0.13.0 is our biggest Spack release yet, with many new major features. From facility deployment to improved environments, microarchitecture support, and auto-generated build farms, this release has features for all of our users.

Spack grew by over 700 packages in the past year, and the project now has over 450 contributors. Thanks to all of you for making this release possible.

Major new core features

Chaining: use dependencies from external "upstream" Spack instances
Environments now behave more like virtualenv/conda
- Each env has a view: a directory with all packages symlinked in
- Activating an environment sets PATH, LD_LIBRARY_PATH, CPATH, CMAKE_PREFIX_PATH, PKG_CONFIG_PATH, etc. to point to this view.
Spack detects and builds specifically for your microarchitecture
- named, understandable targets like skylake, broadwell, power9, zen2
- Spack knows which compilers can build for which architectures
- Packages can easily query support for features like avx512 and sse3
- You can pick a target with, e.g. spack install foo target=icelake
Spack stacks: combinatorial environments for facility deployment
- Environments can now build cartesian products of specs (with matrix:)
- Conditional syntax support to exclude certain builds from the stack
Projections: ability to build easily navigable symlink trees environments
Support no-source packages (BundlePackage) to aggregate related packages
Extensions: users can write custom commands that live outside of Spack repo
Support ARM and Fujitsu compilers

CI/build farm support

spack release-jobs can detect package.py changes and generate .gitlab-ci.yml to create binaries for an environment or stack in parallel (initial support -- will change in future release).
Results of build pipelines can be uploaded to a CDash server.
Spack can now upload/fetch from package mirrors in Amazon S3

New commands/options

spack mirror create --all downloads all package sources/resources/patches
spack dev-build runs phases of the install pipeline on the working directory
spack deprecate permanently symlinks an old, unwanted package to a new one
spack verify chcecks that packages' files match what was originally installed
spack find --json prints JSON that is easy to parse with, e.g. jq
spack find --format FORMAT allows you to flexibly print package metadata
spack spec --json prints JSON version of spec.yaml

Selected improvements

Auto-build requested compilers if they do not exist
Spack automatically adds RPATHs needed to make executables find compiler runtime libraries (e.g., path to newer libstdc++ in icpc or g++)
setup-env.sh is now compatible with Bash, Dash, and Zsh
Spack now caps build jobs at min(16, ncores) by default
spack compiler find now also throttles number of spawned processes
Spack now writes stage directories directly to $TMPDIR instead of symlinking stages within $spack/var/spack/cache.
Improved and more powerful spec format strings
You can pass a spec.yaml file anywhere in the CLI you can type a spec.
Many improvements to binary caching
Gradually supporting new features from Environment Modules v4
spack edit respects VISUAL environment variable
Simplified package syntax for specifying build/run environment modifications
Numerous improvements to support for environments across Spack commands
Concretization improvements

Documentation

Multi-lingual documentation (Started a Japanese translation)
Tutorial now has its own site at spack-tutorial.readthedocs.io
- This enables us to keep multiple versions of the tutorial around

Deprecations

Spack no longer supports dotkit (LLNL's homegrown, now deprecated module tool)
spack build, spack configure, spack diy deprecated in favor of spack dev-build and spack install

Important package changes

3,563 total packages (718 added since 0.12.1)
Spack now defaults to Python 3 (previously preferred 2.7 by default)
Much improved ARM support thanks to Fugaku (RIKEN) and SNL teams
Support new special versions: master, trunk, and head (in addition to develop)
Better finding logic for libraries and headers

v0.12.1 (2018-11-13)

This is a minor bugfix release, with a minor fix in the tutorial and a flake8 fix.

Bugfixes

Add r back to regex strings in binary distribution
Fix gcc install version in the tutorial

v0.12.0 (2018-11-13)

Major new features

Spack environments
spack.yaml and spack.lock files for tracking dependencies
Custom configurations via command line
Better support for linking Python packages into view directories
Packages have more control over compiler flags via flag handlers
Better support for module file generation
Better support for Intel compilers, Intel MPI, etc.
Many performance improvements, improved startup time

License

As of this release, all of Spack is permissively licensed under Apache-2.0 or MIT, at the user's option.
Consents from over 300 contributors were obtained to make this relicense possible.
Previous versions were distributed under the LGPL license, version 2.1.

New packages

Over 2,900 packages (800 added since last year)

Spack would not be possible without our community. Thanks to all of our contributors for the new features and packages in this release!

v0.11.2 (2018-02-07)

This release contains the following fixes:

Fixes for gfortran 7 compiler detection (#7017)
Fixes for exceptions thrown during module generation (#7173)

v0.11.1 (2018-01-19)

This release contains bugfixes for compiler flag handling. There were issues in v0.11.0 that caused some packages to be built without proper optimization.

Fixes:

Issue #6999: FFTW installed with Spack 0.11.0 gets built without optimisations

Includes:

PR #6415: Fixes for flag handling behavior
PR #6960: Fix type issues with setting flag handlers
880e319: Upstream fixes to list_url in various R packages

v0.11.0 (2018-01-17)

Spack v0.11.0 contains many improvements since v0.10.0. Below is a summary of the major features, broken down by category.

New packages

Spack now has 2,178 packages (from 1,114 in v0.10.0)
Many more Python packages (356) and R packages (471)
48 Exascale Proxy Apps (try spack list -t proxy-app)

Core features for users

Relocatable binary packages (spack buildcache, #4854)
Spack now fully supports Python 3 (#3395)
Packages can be tagged and searched by tags (#4786)
Custom module file templates using Jinja (#3183)
spack bootstrap command now sets up a basic module environment (#3057)
Simplified and better organized help output (#3033)
Improved, less redundant spack install output (#5714, #5950)
Reworked spack dependents and spack dependencies commands (#4478)

Major new features for packagers

Multi-valued variants (#2386)
New conflicts() directive (#3125)
New dependency type: test dependencies (#5132)
Packages can require their own patches on dependencies (#5476)
- depends_on(..., patches=<patch list>)
Build interface for passing linker information through Specs (#1875)
- Major packages that use blas/lapack now use this interface
Flag handlers allow packages more control over compiler flags (#6415)
Package subclasses support many more build systems:
- autotools, perl, qmake, scons, cmake, makefile, python, R, WAF
- package-level support for installing Intel HPC products (#4300)
spack blame command shows contributors to packages (#5522)
spack create now guesses many more build systems (#2707)
Better URL parsing to guess package version URLs (#2972)
Much improved PythonPackage support (#3367)

Core

Much faster concretization (#5716, #5783)
Improved output redirection (redirecting build output works properly #5084)
Numerous improvements to internal structure and APIs

Tutorials & Documentation

Many updates to documentation
New tutorial material from SC17
- configuration
- build systems
- build interface
- working with module generation
Documentation on docker workflows and best practices

Selected improvements and bug fixes

No longer build Python eggs -- installations are plain directories (#3587)
Improved filtering of system paths from build PATHs and RPATHs (#2083, #3910)
Git submodules are properly handled on fetch (#3956)
Can now set default number of parallel build jobs in config.yaml
Improvements to setup-env.csh (#4044)
Better default compiler discovery on Mac OS X (#3427)
- clang will automatically mix with gfortran
Improved compiler detection on Cray machines (#3075)
Better support for IBM XL compilers
Better tab completion
Resume gracefully after prematurely terminated partial installs (#4331)
Better mesa support (#5170)

Spack would not be possible without our community. Thanks to all of our contributors for the new features and packages in this release!

v0.10.0 (2017-01-17)

This is Spack v0.10.0. With this release, we will start to push Spack releases more regularly. This is the last Spack release without automated package testing. With the next release, we will begin to run package tests in addition to unit tests.

Spack has grown rapidly from 422 to 1,114 packages, thanks to the hard work of over 100 contributors. Below is a condensed version of all the changes since v0.9.1.

Packages

Grew from 422 to 1,114 packages
- Includes major updates like X11, Qt
- Expanded HPC, R, and Python ecosystems

Core

Major speed improvements for spack find and concretization
Completely reworked architecture support
- Platforms can have front-end and back-end OS/target combinations
- Much better support for Cray and BG/Q cross-compiled environments
Downloads are now cached locally
Support installations in deeply nested directories: patch long shebangs using sbang

Basic usage

Easier global configuration via config.yaml
- customize install, stage, and cache locations
Hierarchical configuration scopes: default, site, user
- Platform-specific scopes allow better per-platform defaults
Ability to set cflags, cxxflags, fflags on the command line
YAML-configurable support for both Lmod and tcl modules in mainline
spack install supports --dirty option for emergencies

For developers

Support multiple dependency types: build, link, and run
Added Package base classes for custom build systems
- AutotoolsPackage, CMakePackage, PythonPackage, etc.
- spack create now guesses many more build systems
Development environment integration with spack setup
New interface to pass linking information via spec objects
- Currently used for BLAS/LAPACK/SCALAPACK libraries
- Polymorphic virtual dependency attributes: spec['blas'].blas_libs

Testing & Documentation

Unit tests run continuously on Travis CI for Mac and Linux
Switched from nose to pytest for unit tests.
- Unit tests take 1 minute now instead of 8
Massively expanded documentation
Docs are now hosted on spack.readthedocs.io

Files

CHANGELOG.md

Latest commit

History

CHANGELOG.md

File metadata and controls

v0.22.0 (2024-05-12)

Features in this release

New commands, options, and directives

Performance improvements

Other new features of note

Binary caches

Removals, deprecations, and syntax changes

Notable Bugfixes

Spack community stats

v0.21.2 (2024-03-01)

Bugfixes

Package updates

v0.21.1 (2024-01-11)

New features

Bugfixes

Package updates

v0.21.0 (2023-11-11)

Features in this release

Other new commands and directives

Performance improvements

Other new features of note

Windows

Notable refactors

Binary cache and stack updates

Removals, deprecations, and syntax changes

Notable Bugfixes

Spack community stats

v0.20.3 (2023-10-31)

Bugfixes

v0.20.2 (2023-10-03)

Features in this release

Bugfixes

v0.20.1 (2023-07-10)

Spack Bugfixes

v0.20.0 (2023-05-21)

Features in this release

Other new commands and directives

Other new features of note

Notable refactors

Binary cache and stack updates

Removals, Deprecations, and disablements

Notable Bugfixes

Spack community stats

v0.19.1 (2023-02-07)

Spack Bugfixes

v0.19.0 (2022-11-11)

Major features in this release

Other new features of note

Performance Improvements

New binary caches and stacks

Removals and Deprecations

Notable Bugfixes

Spack community stats

v0.18.1 (2022-07-19)

Spack Bugfixes

Package updates

v0.18.0 (2022-05-28)

Major features in this release

Other new features of note

Major internal refactors

Performance Improvements

Archspec improvements

Removals and Deprecations

Notable Bugfixes

Packages

Spack community stats

v0.17.3 (2022-07-14)

Spack bugfixes

v0.17.2 (2022-04-13)

Spack bugfixes

v0.17.1 (2021-12-23)

Spack Bugfixes

Package bugfixes

v0.17.0 (2021-11-05)