https://issues.dlang.org/show_bug.cgi?id=22744
Issue ID: 22744 Summary: ImportC: builtins defined in __builtins.di cause undefined symbol linker errors. Product: D Version: D2 Hardware: x86_64 OS: Mac OS X Status: NEW Keywords: ImportC Severity: normal Priority: P1 Component: druntime Assignee: nob...@puremagic.com Reporter: dave287...@gmail.com `__builtin_inf()`, `__builtin_inff()` and `__builtin_infl()` will result in an undefined symbol error if used in C code. For example: // test.c static inline int isfinite(float x){ return x == x && __builtin_fabsf(x) != __builtin_inff(); } int main(){ return isfinite(3.2f); } $ dmd test.c Undefined symbols for architecture x86_64: "__D10__builtins14__builtin_inffFZf", referenced from: _isfinite in test.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) Error: linker exited with status 1 --