diff options
Diffstat (limited to 'math/math.h')
| -rw-r--r-- | math/math.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/math/math.h b/math/math.h index e21708045a..dea8dbe1ae 100644 --- a/math/math.h +++ b/math/math.h @@ -442,8 +442,12 @@ enum /* Return nonzero value if X is positive or negative infinity. */ # if __HAVE_DISTINCT_FLOAT128 && !__GNUC_PREREQ (7,0) \ - && !defined __SUPPORT_SNAN__ - /* __builtin_isinf_sign is broken for float128 only before GCC 7.0. */ + && !defined __SUPPORT_SNAN__ && !defined __cplusplus + /* Since __builtin_isinf_sign is broken for float128 before GCC 7.0, + use the helper function, __isinff128, with older compilers. This is + only provided for C mode, because in C++ mode, GCC has no support + for __builtin_types_compatible_p (and when in C++ mode, this macro is + not used anyway, because libstdc++ headers undefine it). */ # define isinf(x) \ (__builtin_types_compatible_p (__typeof (x), _Float128) \ ? __isinff128 (x) : __builtin_isinf_sign (x)) |