- check the version of `/usr/bin/ld` for support of `-no_fixup_chains`
- check for usage of the `-fuse-ld` flag, since this flag is only
supported by Apple ld64
Also, call `no_fixup_chains` when setting up the build environment.
Invoking `ld` with `-undefined dynamic_lookup` emits a warning starting
Xcode 14:
ld: warning: -undefined dynamic_lookup may not work with chained fixups
Chained fixups is a linker optimisation that results in faster binary
load times, and is enabled by default starting Xcode 13 when the target
is macOS 12 or newer.
However, this interacts poorly with `-undefined dynamic_lookup`, and
Xcode will disable chained fixups when it is invoked with this flag
starting Xcode 14.3. Until then, we may be shipping binaries that are
broken in subtle ways, so let's disable chained fixups when necessary
instead.
I patterned the changes here after the handling of `-no_weak_imports`.
The only difference is that we need to check the flags that were passed
to the linker first to see if we do need to disable chained fixups.
For additional context, see:
https://developer.apple.com/documentation/xcode-release-notes/xcode-13-release-noteshttps://www.wwdcnotes.com/notes/wwdc22/110362/https://www.emergetools.com/blog/posts/iOS15LaunchTimehttps://github.com/python/cpython/issues/97524https://github.com/pybind/pybind11/pull/4301
One of the more curious bugs, if you use
-Wl,-headerpad_max_install_names on linux, it tries to link a library
named "eaderpath_max_install_names" in, which causes all kinds of weird
havoc.
Most notably, gtester inside glib fails to run for bizarre reasons.
-Wl,-headerpad_max_install_names is not an option anywhere outside macos
anyway, so move it to macos only and avoid the heartache of extremely
weild bugs.
This probably has to wait until 2.7.0 now and will require a bunch of
formula changes/deprecations but we should probably start moving in this
direction given we're not installing any of these on our CI any more.
