https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113679
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |DUPLICATE
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
[apinski@xeond2 gcc]$ ~/upstream-gcc/bin/gcc -m32 tr56.c
[apinski@xeond2 gcc]$ ./a.out
-2.000000
[apinski@xeond2 gcc]$ ~/upstream-gcc/bin/gcc -m32 tr56.c
-fexcess-precision=standard
[apinski@xeond2 gcc]$ ./a.out
0.000000
[apinski@xeond2 gcc]$ ~/upstream-gcc/bin/gcc -m32 tr56.c -msse2 -mfpmath=sse
[apinski@xeond2 gcc]$ ./a.out
0.000000
Yes it is due to excessive precision of x87. Use either
`-fexcess-precision=standard` or `-msse2 -mfpmath=sse` if you don't want to use
the execessive precision of the x87 FP.
*** This bug has been marked as a duplicate of bug 323 ***
