diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc index b155611578d..8fc01cdfb77 100644 --- a/gcc/fold-const.cc +++ b/gcc/fold-const.cc @@ -1305,6 +1305,17 @@ const_binop (enum tree_code code, tree arg1, tree arg2) inexact = real_arithmetic (&value, code, &d1, &d2); real_convert (&result, mode, &value); + /* Don't constant fold this floating point operation if + both operands are not NaN but the result is NaN, and + flag_trapping_math. Such operations should raise an + invalid operation exception. */ + if (flag_trapping_math + && MODE_HAS_NANS (mode) + && REAL_VALUE_ISNAN (result) + && !REAL_VALUE_ISNAN (d1) + && !REAL_VALUE_ISNAN (d2)) + return NULL_TREE; + /* Don't constant fold this floating point operation if the result has overflowed and flag_trapping_math. */ if (flag_trapping_math diff --git a/gcc/testsuite/gcc.dg/pr95115.c b/gcc/testsuite/gcc.dg/pr95115.c new file mode 100644 index 00000000000..46a95dfb698 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr95115.c @@ -0,0 +1,25 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -ftrapping-math" } */ +/* { dg-add-options ieee } */ +/* { dg-require-effective-target fenv_exceptions } */ + +#include +#include + +double +x (void) +{ + double d = __builtin_inf (); + return d / d; +} + +int +main (void) +{ + double r = x (); + if (!__builtin_isnan (r)) + abort (); + if (!fetestexcept (FE_INVALID)) + abort (); + exit (0); +}