https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107608
--- Comment #31 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Aldy Hernandez <al...@gcc.gnu.org>: https://gcc.gnu.org/g:844190af178c210a6aff6b7eb4dd8c6a49210ff9 commit r13-5179-g844190af178c210a6aff6b7eb4dd8c6a49210ff9 Author: Aldy Hernandez <al...@redhat.com> Date: Tue Jan 10 10:57:16 2023 +0100 [PR107608] [range-ops] Avoid folding into INF when flag_trapping_math. As discussed in the PR, for trapping math, do not fold overflowing operations into +-INF as doing so could elide a trap. There is a minor adjustment to known_isinf() where it was mistakenly returning true for an [infinity U NAN], whereas it should only return true when the range is exclusively +INF or -INF. This is benign, as there were no users of known_isinf up to now. Tested on x86-64 Linux. I also ran the glibc testsuite (git sources) on x86-64 and this patch fixes: -FAIL: math/test-double-lgamma -FAIL: math/test-double-log1p -FAIL: math/test-float-lgamma -FAIL: math/test-float-log1p -FAIL: math/test-float128-catan -FAIL: math/test-float128-catanh -FAIL: math/test-float128-lgamma -FAIL: math/test-float128-log -FAIL: math/test-float128-log1p -FAIL: math/test-float128-y0 -FAIL: math/test-float128-y1 -FAIL: math/test-float32-lgamma -FAIL: math/test-float32-log1p -FAIL: math/test-float32x-lgamma -FAIL: math/test-float32x-log1p -FAIL: math/test-float64-lgamma -FAIL: math/test-float64-log1p -FAIL: math/test-float64x-lgamma -FAIL: math/test-ldouble-lgamma PR tree-optimization/107608 gcc/ChangeLog: * range-op-float.cc (range_operator_float::fold_range): Avoid folding into INF when flag_trapping_math. * value-range.h (frange::known_isinf): Return false for possible NANs.