[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #10 from Marc Glisse --- Flags like -ftrapping-math can prevent gcc from folding at compile-time when the result is infinite (or maybe it always refuses to fold in that case). In your example, gcc generates a runtime call to __muldc3

[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 Paul Zimmermann changed: What|Removed |Added CC||zimmerma+gcc at loria dot fr ---

[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 boger at us dot ibm.com changed: What|Removed |Added CC||boger at us dot ibm.com ---

[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #6 from boger at us dot ibm.com --- If the last comment is true, does that mean the fold_const.c file in gcc should be built in a way so that it doesn't use the fma, like using some kind of option during the build of gcc at least for

[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 David Edelsohn dje at gcc dot gnu.org changed: What|Removed |Added Target|ppc64-ibm-linux,|s390x-ibm-linux,

[Bug target/60181] constant folding of complex number incorrect

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #8 from Andrew Pinski pinskia at gcc dot gnu.org --- (In reply to boger from comment #6) If the last comment is true, does that mean the fold_const.c file in gcc should be built in a way so that it doesn't use the fma, like using

[Bug target/60181] constant folding of complex number incorrect

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #2 from Richard Biener rguenth at gcc dot gnu.org --- I think that it needs to be decided on a case-by-case basis whether the runtime complex division routine is precise enough. But yes, you generally cannot expect constant folding

[Bug target/60181] constant folding of complex number incorrect

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #3 from Andreas Krebbel krebbel at gcc dot gnu.org --- I'll keep the bugreport open with low prio. If I find the time I will at least try to understand what's going on before closing it. The testcase is extracted from

[Bug target/60181] constant folding of complex number incorrect

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #4 from Andrew Pinski pinskia at gcc dot gnu.org --- Could this because of the use of fma for s390 and PPC inside the division code?

[Bug target/60181] constant folding of complex number incorrect

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60181 --- Comment #1 from joseph at codesourcery dot com joseph at codesourcery dot com --- There are no specified accuracy requirements for complex multiplication / division, even under Annex G (parts of which - imaginary types in particular - are