Use __builtin_signbit directly instead of std::signbit. libstdc++-v3/ChangeLog:
* include/std/complex (arg(T)): Use __builtin_signbit instead of std::signbit. --- This would avoid overload resolution for std::signbit, and avoid a function call for -O0, but I'm not sure it's worth bothering. Tested x86_64-linux. libstdc++-v3/include/std/complex | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/std/complex b/libstdc++-v3/include/std/complex index 67f37d4ec2b7..d9d2d8afda89 100644 --- a/libstdc++-v3/include/std/complex +++ b/libstdc++-v3/include/std/complex @@ -2532,8 +2532,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { typedef typename __gnu_cxx::__promote<_Tp>::__type __type; #if (_GLIBCXX11_USE_C99_MATH && !_GLIBCXX_USE_C99_FP_MACROS_DYNAMIC) - return std::signbit(__x) ? __type(3.1415926535897932384626433832795029L) - : __type(); + return __builtin_signbit(__type(__x)) + ? __type(3.1415926535897932384626433832795029L) : __type(); #else return std::arg(std::complex<__type>(__x)); #endif -- 2.49.0