llvm-project

353d6a98 - [libc++] Conditionally declare `lgamma_r` as noexcept (#156547)

[libc++] Conditionally declare `lgamma_r` as noexcept (#156547) An older PR https://github.com/llvm/llvm-project/pull/102036 suggested that LLVM libc declares `lgamma_r` as noexcept and is incompatible with this redeclaration. However, I recently discovered that glibc also declares the math functions to be noexcept under C++ mode. This line usually don't cause issues because both the glibc and this file are included as "system headers". According to [this godbolt](https://godbolt.org/z/o7Wd9PP58), both GCC and clang ignore the different exception specification between multiple declarations if they are in system headers. However, this seems not the case for NVCC/EDG, so a fix for this redeclaration is still desirable. This patch proposes that we should declare the function as noexcept under known libc integrations to keep the declared function consistent.