It would be nice to reuse some of the macro structure for internal
functions, like `rem_pio2`. To facilitate this, add a `public` field and
make it available in the macro's API.
The published crates fail to build with an edition less than 2024
because they are packaged with `resolver = "3"`, which is a 2024-only
option. Revert back to resolver v2 to drop this requirement.
Fixes: https://github.com/rust-lang/compiler-builtins/issues/883
`compiler-builtins` uses `public-test-deps`, `libm` uses
`unstable-public-internals`. Consolidate these under the `libm` name.
Once compiler-builtins is no longer published, this feature can probably
be dropped.
Also switch to `dep:` syntax for features that enable dependencies.
compiler-builtins currently wouldn't publish correctly because of a
relative path to `libm` that doesn't get included in the package. Fix
this by simlinking `libm` to within the `compiler-builtins` directory.
Also symlink LICENSE.txt which lets us drop the `include` array in
Cargo.toml. LICENSE.txt and compiler-rt were not being included anyway,
since Cargo silently drops items that are not within the crate
directory.
In order to disambiguate things now that libm is part of the
compiler-builtins repository, do the following:
* Mention libm in LICENSE.txt
* Clarify the default license for crates other than libm and
compiler-builtins
* Add an explicit license field to Cargo.toml for all other crates
Many contributions to compiler-builtins don't have any need to touch
libm, and could get by with the few minutes of CI for compiler-builtins
rather than the ~30 minutes for libm. We already have some scripts that
handle changed file detection, so expand its use to skip libm CI if it
doesn't need to run.
Set the submodule to the same version we had been using in
rust-lang/libm. This is a downgrade from the current version but it
avoids some new deviations that show up, which can be corrected later.
Update `run.sh` to start testing `libm`. Currently this is somewhat
inefficient because `builtins-test` gets run more than once on some
targets; this can be cleaned up later.
This crate doesn't need to be a default member since it requires the
opposite settings from everything else. Exclude it from the workspace
and run it only when explicitly requested.
This also makes `cargo t --no-default-features` work without additional
qualifiers. `--no-default-features` still needs to be passed to ensure
`#![compiler_builtins]` does not get set.
compiler-builtins needs doctests disabled in order for everything to
work correctly, since this causes an error running rustdoc that is
unrelated to features (our `compiler_builtins` is getting into the crate
graph before that from the sysroot, but `#![compiler_builtins]` is not
set).
We can also remove `test = false` and `doctest = false` in
`builtins-test` since these no longer cause issues. This is unlikely to
be used but it is better to not quietly skip if anything ever gets added
by accident.
Use the 2024 style edition for all crates and enable import sorting.
2024 already applies some smaller heuristics that look good in
compiler-builtins, I have dropped `use_small_heuristics` that was set in
`libm` because it seems to negatively affect the readibility of anything
working with numbers (e.g. collapsing multiple small `if` expressions
into a single line).
Distribute everything from `libm/` to better locations in the repo.
`libm/libm/*` has not moved yet to avoid Git seeing the move as an edit
to `Cargo.toml`.
Files that remain to be merged somehow are in `etc/libm`.
Absorb the libm repository into `compiler-builtins`.
This was done using `git-filter-repo` to ensure hashes mentioned in
commit messages were correctly rewritten, I used the same strategy to
merge `ctest` into `libc` [1] and it worked quite well. Approximately:
# `git filter-repo` requires a clean clone
git clone https://github.com/rust-lang/libm.git
# Move all code to a `libm` subdirectory for all history
git filter-repo --to-subdirectory-filter libm
# The default merge messages are "merge pull request #nnn from
# user/branch". GH links these incorrectly in the new repo, so
# rewrite messages from `#nnn` to `rust-lang/libm#nnn`.
echo 'regex:(^|\s)(#\d+)==>\1rust-lang/libm\2' > messages.txt
git filter-repo --replace-message messages.txt
# Re-add a remote and push as a new branch
git remote add upstream https://github.com/rust-lang/libm.git
git switch -c merge-into-builtins-prep
git push --set-upstream upstream merge-into-builtins-prep
# Now in a compiler-builtins, add `libm` as a remote
git remote add libm https://github.com/rust-lang/libm.git
git fetch libm
# Do the merge that creates this commit
git merge libm/merge-into-builtins-prep --allow-unrelated-histories
The result should be correct git history and blame for all files, with
messages that use correct rewritten hashes when they are referenced.
There is some reorganization and CI work needed, but that will be a
follow up.
After this merges I will need to push tags from `libm`, which I have
already rewritten to include a `libm-` prefix. Old tags in
compiler-builtins should likely also be rewritten to add a prefix (we
already have this for newer tags), but this can be done at any point.
* Original remote: https://github.com/rust-lang/libm.git
* Default HEAD: c94017af75c3ec4616d5b7f9b6b1b3826b934469 ("Migrate all
crates except `libm` to edition 2024")
* HEAD after rewriting history: 15fb6307f6dc295fb965d1c4f486571cc18ab6b3
("Migrate all crates except `libm` to edition 2024")
[1]: https://github.com/rust-lang/libc/pull/4283#issuecomment-2773986492
Prepare for having the repositories combined by ensuring EMULATED,
RUST_BACKTRACE, and CI are set or forwarded as applicable. Also
re-indent the file to four spaces and do some reorganization.
