Having multiple compilers in the build environment would result in an
invalid LD_DYLD_PATH like /usr/lib/dyld/usr/lib/dyld.
Since the path is hardcoded in XNU it can't be anything but
/usr/lib/dyld anyway.
This fixes a bug introduced in #27831: `for path in "$dir"/lib*.so` assumed that
all libs match `lib*.so`, but 07674788d6 started
adding libs that match `*.so` and `*.so.*`.
Now is an opportune time to do this, as the infixSalt conversion in
`add-flags.sh` ensures that all the relevant `NIX_*` vars will be
defined even if empty.
This is basically a sed job, in preparation of the next commit. The
rules are more or less:
- s"NIX_(.._WRAPPER_)?([a-zA-Z0-9@]*)"NIX_\1@infixSalt@_\2"g
- except for non-cc-wrapper-specific vars like `NIX_DEBUG`
This is an ugly temp hack for cross compilation, but now we have something better on the way.
Bind `infixSalt` as an environment variable as it will be used in it.
Unified processing of command line arguments in ld-wrapper broke support for
`NIX_DONT_SET_RPATH` and revealed that ld-wrapper adds the directory of its
`-plugin` argument to runpath. This pull request fixes that. It treats
`dir/libname.so` as `-L dir -l name`, because this is how `ld.so` interprets
resulting binary: with `dir` in `RUNPATH` and the bare `libname.so` (without
`dir`) in `NEEDED`, it looks for `libname.so` in each `RUNPATH` and chooses the
first, even when the linker was invoked with an absolute path to `.so`.
As described in https://github.com/NixOS/nixpkgs/issues/18461, MacOS no
longer accepts dylibs which only reexport other dylibs, because their
symbol tables are empty. To get around this, we define an object file
with a single "private extern" symbol, which hopefully won't clobber
anything.
The time to expand rpath was proportional to the number of -L flags times the
number of -l flags. Now it is proportional to their sum (assuming constant
number of files in each directory in an -L flag).
Issue reported by @nh2 at https://github.com/NixOS/nixpkgs/issues/27609#issuecomment-317916623
As @oxij points out in [1], this breakage is especially serious because
it changes the contents of built environments without a corresonding
change in their hashes. Also, the revert is easier than I thought.
This reverts commit 3cb745d5a6.
[1]: https://github.com/NixOS/nixpkgs/pull/27427#issuecomment-317293040
Besides deduplicating overlapping logic, clear warning messages were
added for:
- No glob/path for dynamic linker provided (use default glob)
- Glob did not expand to anything (don't append flag)
- glob expanded to multiple things (take first, like before)
This makes those files a bit easier to read. Also, for what it's worth,
it brings us one baby step closer to handling spaces in store paths.
Also, I optimized handling of many transitive deps with read. Probably,
not very beneficial, but nice to enforce the pkg-per-line structure.
Doing so let me find much dubious code and fix it.
Two misc notes:
- `propagated-user-env-packages` also needed to be adjusted as
sometimes it is copied to/from the propagated input files.
- `local fd` should ensure that file descriptors aren't clobbered
during recursion.