rust/library/std
Matthias Krüger 5c63363284
Rollup merge of #128388 - beetrees:f16-f128-slightly-improve-windows-abi, r=tgross35
Match LLVM ABI in `extern "C"` functions for `f128` on Windows

As MSVC doesn't support `_Float128`, x86-64 Windows doesn't have a defined ABI for `f128`. Currently, Rust will pass and return `f128` indirectly for `extern "C"` functions. This is inconsistent with LLVM, which passes and returns `f128` in XMM registers, meaning that e.g. the ABI of `extern "C"` compiler builtins won't match. This PR fixes this discrepancy by making the x86-64 Windows `extern "C"` ABI pass `f128` directly through to LLVM, so that Rust will follow whatever LLVM does. This still leaves the difference between LLVM and GCC (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115054) but this PR is still an improvement as at least Rust is now consistent with it's primary codegen backend and compiler builtins from `compiler-builtins` will now work.

I've also fixed the x86-64 Windows `has_reliable_f16` match arm in `std` `build.rs` to refer to the correct target, and added an equivalent match arm to `has_reliable_f128` as the LLVM-GCC ABI difference affects both `f16` and `f128`.

Tracking issue: #116909

try-job: x86_64-msvc
try-job: x86_64-mingw
2024-07-31 15:36:31 +02:00
..
benches Reformat use declarations. 2024-07-29 08:26:52 +10:00
src Rollup merge of #128387 - liigo:patch-14, r=tgross35 2024-07-31 15:36:31 +02:00
tests Reformat use declarations. 2024-07-29 08:26:52 +10:00
build.rs Match LLVM ABI in extern "C" functions for f128 on Windows 2024-07-30 20:23:33 +01:00
Cargo.toml Auto merge of #125016 - nicholasbishop:bishop-cb-112, r=tgross35 2024-07-29 07:41:33 +00:00