[Bug c++/109344] feraiseexcept produces incorrect code when optimizations are enabled
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109344 --- Comment #5 from Xi Ruoyao --- (In reply to albin from comment #4) > Thanks for the info. If it was fixed three years ago how come it is still > seen when using gcc (trunk) on Compiler Explorer? Is Compiler Explorer using > an obsolete glibc? It uses Glibc-2.31: https://godbolt.org/z/h348q7fbh
[Bug c++/109344] feraiseexcept produces incorrect code when optimizations are enabled
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109344 --- Comment #4 from albin --- Thanks for the info. If it was fixed three years ago how come it is still seen when using gcc (trunk) on Compiler Explorer? Is Compiler Explorer using an obsolete glibc?
[Bug c++/109344] feraiseexcept produces incorrect code when optimizations are enabled
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109344 Xi Ruoyao changed: What|Removed |Added Resolution|--- |INVALID Status|UNCONFIRMED |RESOLVED --- Comment #3 from Xi Ruoyao --- INVALID then.
[Bug c++/109344] feraiseexcept produces incorrect code when optimizations are enabled
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109344
Jakub Jelinek changed:
What|Removed |Added
CC||jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek ---
I get the same result for all of -O0/-O1/-O2, all 3 functions raise both
exceptions and that is correct, glibc has removed the inline versions some time
ago:
https://sourceware.org/pipermail/libc-alpha/2020-March/111753.html
The bug was on the glibc side:
both the
/* One example of an invalid operation is 0.0 / 0.0. */
float __f = 0.0;
# ifdef __SSE_MATH__
__asm__ __volatile__ ("divss %0, %0 " : : "x" (__f));
and
float __f = 1.0;
float __g = 0.0;
# ifdef __SSE_MATH__
__asm__ __volatile__ ("divss %1, %0" : : "x" (__f), "x" (__g));
part, because glibc didn't tell the compiler the inline assembly actually
modifies the register.
So, the first one was supposed to be
__asm__ __volatile__ ("divss %0, %0 " : "+x" (__f));
and the second
__asm__ __volatile__ ("divss %1, %0" : "+x" (__f) : "x" (__g));
Not a bug on the GCC side and on glibc side it has been fixed by the removal of
the inline version.
[Bug c++/109344] feraiseexcept produces incorrect code when optimizations are enabled
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109344 Xi Ruoyao changed: What|Removed |Added CC||xry111 at gcc dot gnu.org --- Comment #1 from Xi Ruoyao --- Why should the second and third function only raise FE_INVALID?
