[libc-commits] [libc] [llvm] [libc][math] Refactor log10, log1p, log2 implementation to header-only in src/__support/math folder. (PR #176089)

[Nico Weber via libc-commits]

nico wrote:

I eventually got gcc 12.4 (not 12.2) off homebrew. But cmake doesn't complete with gcc on mac (#176680), and arm_acle.h doesn't seem to build (which is used by libm):

```
% cat acle.cc      
#include <arm_acle.h>
```

```
% gcc-12 -c acle.cc
In file included from acle.cc:1:
/Users/thakis/src/homebrew/Cellar/gcc at 12/12.4.0/lib/gcc/12/gcc/aarch64-apple-darwin24/12/include/arm_acle.h: In function 'int __rndr(uint64_t*)':
/Users/thakis/src/homebrew/Cellar/gcc at 12/12.4.0/lib/gcc/12/gcc/aarch64-apple-darwin24/12/include/arm_acle.h:282:34: error: invalid conversion from 'uint64_t*' {aka 'long long unsigned int*'} to 'long unsigned int*' [-fpermissive]
  282 |   return __builtin_aarch64_rndr (__res);
      |                                  ^~~~~
      |                                  |
      |                                  uint64_t* {aka long long unsigned int*}
<built-in>: note:   initializing argument 1 of 'int __builtin_aarch64_rndr(long unsigned int*)'
/Users/thakis/src/homebrew/Cellar/gcc at 12/12.4.0/lib/gcc/12/gcc/aarch64-apple-darwin24/12/include/arm_acle.h: In function 'int __rndrrs(uint64_t*)':
/Users/thakis/src/homebrew/Cellar/gcc at 12/12.4.0/lib/gcc/12/gcc/aarch64-apple-darwin24/12/include/arm_acle.h:289:36: error: invalid conversion from 'uint64_t*' {aka 'long long unsigned int*'} to 'long unsigned int*' [-fpermissive]
  289 |   return __builtin_aarch64_rndrrs (__res);
      |                                    ^~~~~
      |                                    |
      |                                    uint64_t* {aka long long unsigned int*}
<built-in>: note:   initializing argument 1 of 'int __builtin_aarch64_rndrrs(long unsigned int*)'
```

It feels like nobody's really building libm with gcc on a mac. Is linux required to be able to make libm patches?

https://github.com/llvm/llvm-project/pull/176089