Prior to this change we would assume the ABI for Apple targets to
be GNU which could result in subtle errors in LLVM emitting calls
to non-existent system libc provided functions such as `_sincosf`
which is a GNU extension and as such is not provided by macOS for example.
This would result in linker errors where the linker would not be
able to find the said symbol in `libSystem.tbd`.
With this change, we now correctly identify macOS (and other Apple
platforms) as having ABI `unknown` which translates to unspecified
in LLVM under-the-hood:
```
// main.ll
target triple = "aarch64-unknown-macos-unknown"
```
Note however that we never suffix the target OS with target version
such as `macos11` or `macos12` which means we fail to instruct LLVM
of potential optimisations provided by the OS such as the availability
of function `___sincosf_stret`. I suggest we investigate that in a
follow-up commit.
This was a bit trickier than it should be due to symbol conflicts with
zig's compiler-rt implementation. We attempt to use weak linkage in
our compiler-rt, but this does not seem to be working in all cases. I
manually disabled export of the problematic compiler-rt math functions
in order to cross compile musl's libc.so for all targets as input to
`tools/gen_stubs.zig`.
Other than that, this update went fairly smoothly. Quite a few
additional symbols were added to the blacklist in `tools/gen_stubs.zig`
due to recent reorganization of zig's compiler-rt.
This is a patch to glibc features.h which makes
_DYNAMIC_STACK_SIZE_SOURCE undefined unless the version is >= 2.34.
This feature was introduced with glibc 2.34 and without this patch, code
built against these headers but then run on an older glibc will end up
making a call to sysconf() that returns -1 for the value of SIGSTKSZ
and MINSIGSTKSZ.
Closes#10713
Zig calls it aarch64. Linux calls it arm64. Currently lib/libc/include
has both arm64 and aarch64, which is quite confusing.
tools/update-linux-headers.zig was executed against the latest stable
linux patch version, therefore some other minor header updates. I will
update the wiki on how to do it once this PR is accepted.
This was originally introduced in 4d48948b526337947ef59a83f7dbc81b70aa5723
but broken immediately afterwards in c8af00c66e8b6f62e4dd6ac4d86a3de03e9ea354.
Before this commit, glibc headers did the following mapping:
* (zig) mipsel-linux-gnu => (glibc) mipsel-linux-gnu
* (zig) mipsel-linux-gnu-soft => (glibc) (none)
* (zig) mips-linux-gnu => (glibc) mips-linux-gnu
* (zig) mips-linux-gnu-soft => (glibc) (none)
While the glibc ABI stubs used the (zig) gnueabi and gnueabihf ABIs,
and the stage2 available_libcs array listed:
* (zig) mipsel-linux-gnu
* (zig) mips-linux-gnu
The problem is the mismatch between the ABI component of the headers and
the stubs.
This commit makes the following clarifications:
* (zig) mips-linux-gnueabi means soft-float
* (zig) mipsel-linux-gnueabi means soft-float
* (zig) mips-linux-gnueabihf means hard-float
* (zig) mipsel-linux-gnueabihf means hard-float
Consequently, the glibc headers now do this mapping:
* (zig) mips-linux-gnueabihf => (glibc) mips-linux-gnu
* (zig) mipsel-linux-gnueabihf => (glibc) mipsel-linux-gnu
* (zig) mips-linux-gnueabi => (glibc) mips-linux-gnu-soft
* (zig) mipsel-linux-gnueabi => (glibc) mipsel-linux-gnu-soft
The glibc ABI stubs are unchanged, and the stage2 available_libcs
array's 2 entries are modified and it gains 2 more:
* (zig) mipsel-linux-gnueabi
* (zig) mipsel-linux-gnueabihf
* (zig) mips-linux-gnueabi
* (zig) mips-linux-gnueabihf
Now everything is consistent. Zig no longer recognizes a `mips-linux-gnu`
triple; one must use `mips-linux-gnueabi` (soft float) or
`mips-linux-gnueabihf` (hard float).
similar commit from the past:
c73cd05468fba4bba5762a654aacdd9d90ecd272
This also modifies tools/update-linux-headers.zig to remove these same
files for next time to prevent a regression.
closes#10249
* Add missing Linux headers. Closes#9837
* Update existing headers to latest Linux.
* Consolidate headers that are the same for multiple Zig target CPU
architectures. For example, Linux has only an x86 directory for both
x86_64 and x86 CPU architectures. Now Zig only ships an x86 directory
for Linux headers, and will emit the proper corresponding -isystem
flags.
* tools/update-linux-headers.zig is now available for upgrading to
newer Linux headers, and the update process is now documented on the
wiki.
This commit also corrects a mistake from commit
6dc2236054dfcf911ce848f67a4078740a90783a which did not properly delete
files when upgrading to the 1.2.2 musl headers.
Rename include dir to match the convention:
from `wasm32-wasi` to `wasm-wasi-musl`
Add building stubs which will be used to build and cache WASI
libc sysroot.
The reason this is required is for two reasons: 1) the libc
targeting `aarch64` macOS is slightly newer than that targeting
`x86_64`, and 2) `OSAtomic.h` uses relative imports rather than
system-wide imports for accompanying headers which clearly is an
oversight on Apple's part. Until such time when `libkern` headers
between `x86_64` and `aarch64` are identical, this will require a
manual intervention to duplicate the relevant headers between the
respective architectures.
See #5854
Some tiny tweaks too:
* Use `wasm-freestanding-musl` instead of `wasm32-freestanding-musl`,
making it pointer-size-agnostic.
* Fix trying to build non-existent wasm musl start files.
See ziglang/fetch-them-macos-headers#2 for more details. The path
forward looks like one of the following:
* Ony provide headers for the oldest supported macOS (currently 10.13
but soon to be bumped to 10.14).
* Provide headers for multiple versions, and select based on the Zig
target OS version range minimum.
* Don't try to provide macOS headers.
If we don't tackle the version problem, we would have to re-introduce
the ability to detect and depend on native system headers if we wanted
to support C/C++ code that used newer OS definitions.
This patch also adds support for `#include <mach/mach_time.h>`.
Also related: #5236
these new files are generated by recursively including:
sysexits.h
mach/mach.h
sys/attr.h
sys/mount.h
crt_externs.h
execinfo.h
all of which are depended on by LLVM libraries.
