__has_attribute __has_builtin __has_extension __has_feature P99_ATLEAST P99_CONST_FUNCTION P99_DEPRECATED P99_EXPECT p99_extension P99_FIXED_REGISTER p99_has_attribute p99_has_builtin p99_has_extension p99_has_feature P99_IF_COMPILER p99_inline P99_LIKELY P99_MACRO_END P99_PARALLEL_PRAGMA P99_PURE_FUNCTION P99_SETJMP_INLINE P99_STRINGIFY P99_TENTATIVE_DEC P99_TENTATIVE_DEF P99_UNLIKELY P99_VECTOR P99_WARN_UNUSED_RESULT P99_WEAK static_inline

P99_LIKELY #define P99_LIKELY (   ... )    P99_EXPECT(!!(__VA_ARGS__), 1) Mark the conditional expression as being likely. This can be useful e.g to test the return value of printf. Use with care, as humans are particularly bad at branch prediction. If unsure, first test your conditional for some time to see that the case is really as likely as you think. See also P99_EXPECT P99_UNLIKELY Examples test-p99-pow.c. Definition at line 1010 of file p99_compiler.h.