From 06696f40afe58a231e2531c8bf6d9f0dadb92e51 Mon Sep 17 00:00:00 2001 From: Jakob Kaivo Date: Sun, 3 Mar 2019 21:25:50 -0500 Subject: outline details from C18 annex F --- src/math/log10.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'src/math/log10.c') diff --git a/src/math/log10.c b/src/math/log10.c index cea1d45b..e504df44 100644 --- a/src/math/log10.c +++ b/src/math/log10.c @@ -2,11 +2,24 @@ #include #include "_tgmath.h" #include "errno.h" +#include "fenv.h" /** base-10 logarithm **/ TYPE TGFN(log10)(TYPE x) { + switch (fpclassify(x)) { + case FP_ZERO: feraiseexcept(FE_INVALID); return - INFINITY; + case FP_INFINITE: if (!signbit(x)) { return x; } break; + default: break; + } + + if (x == 1.0) { + return 0.0; + } + if (x < 0) { + feraiseexcept(FE_INVALID); + return NAN; errno = EDOM; /* ARGUMENT(x) is negative */ return TGHUGE; } -- cgit v1.2.1