This code
if (!R_FINITE(x)) return x;
expands to
if (!__builtin_isfinite (x)) return x;
It is fixed by adding this to the .c file:
#define __builtin_isfinite finite
Comment #1 by lance — 2023-04-29T21:22:02Z
The compilation error message is
Error: undefined identifier `__builtin_isfinite`
@bachmeil updated dlang/dmd pull request #15147 "Fix 23867 and 23869" fixing this issue:
- Fix issues 23867 and 23869 - define __builtin_isfinite and __builtin_isnan
These GNU C builtins are referenced by macros such as:
* ISNAN
* R_FINITE
https://github.com/dlang/dmd/pull/15147
Comment #4 by dlang-bot — 2023-04-30T23:00:08Z
dlang/dmd pull request #15147 "Fix 23867 and 23869" was merged into master:
- 812fd8a5fa5fb04c5d48e10a57905d5a39f39f13 by Lance Bachmeier:
Fix issues 23867 and 23869 - define __builtin_isfinite and __builtin_isnan
These GNU C builtins are referenced by macros such as:
* ISNAN
* R_FINITE
https://github.com/dlang/dmd/pull/15147