[libcxx-commits] [libcxx] [libc++] P3391R2: `constexpr` integral overloads of `to_(w)string` (PR #205025)

[A. Jiang via libcxx-commits]

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@@ -3774,12 +3777,15 @@ stoull(const string& __str, size_t* __idx = nullptr, int __base = 10);
 [[__nodiscard__]] _LIBCPP_EXPORTED_FROM_ABI double stod(const string& __str, size_t* __idx = nullptr);
 [[__nodiscard__]] _LIBCPP_EXPORTED_FROM_ABI long double stold(const string& __str, size_t* __idx = nullptr);
 
+#  if _LIBCPP_STD_VER < 26 || defined(_LIBCPP_BUILDING_LIBRARY)
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frederick-vs-ja wrote:

`[[gnu::used]]` + `[[gnu::gnu_inline]]` seems problematic at least for GCC.

When `[[gnu::gnu_inline]]` and `[[gnu::used]]` are applied together to a `constexpr` function definition, it seems that we can't keep the out-of-line definition of that function. For Clang, we can only apply `[[gnu::unused]]` to that definition, but GCC rejects mismatch of presence `[[gnu::gnu_inline]]` on different declarations.

https://github.com/llvm/llvm-project/pull/205025