fma(3) Library Functions Manual fma(3) fma fmaf fmal - (libm -lm) #include double fma(double x, double y, double z); float fmaf(float x, float y, float z); long double fmal(long double x, long double y, long double z); glibc ( feature_test_macros(7)): fma() fmaf() fmal(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L x * y + z. ( fenv(3)). x * y + z . x y NaN NaN. x y z NaN. x y 0 z NaN NaN. x y 0 z NaN NaN. x y ( ) z NaN NaN. . 0 . math_error(7) . : : x * y + z x * y . (FE_INVALID). : (FE_OVERFLOW). : (FE_UNDERFLOW). errno. attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |fma(), | | MT-Safe | |fmaf(), | | | |fmal() | | | +------------+------------------------------------+--------------------+ C11, POSIX.1-2008. glibc 2.1. C99 POSIX.1-2001. remainder(3) remquo(3) 3 . . : . 6.18 8 2026 fma(3)