[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #11 from Richard Biener rguenth at gcc dot gnu.org --- (In reply to Vittorio Zecca from comment #10) I just installed gcc-4.9.1 and it still has this bug. It does not even compile itself (divtf3.c) with -Og. As said it will be fixed in 4.9.2. I've double-checked that -Og bootstrap works on the 4.9 branch head - how did you configure/make?
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #12 from Vittorio Zecca zeccav at gmail dot com --- Yes, you did say it will be fixed in 4.9.2. Sorry. I did: export CFLAGS=-ggdb -Og export CXXFLAGS=$CFLAGS ../gcc-4.9.1/configure --prefix=/home/vitti/local/gcc-4.9.1 --disable-lto --with-tune=k8 --enable-languages=c,c++,fortran I compiled manually divtf3.c without -Og.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #10 from Vittorio Zecca zeccav at gmail dot com --- I just installed gcc-4.9.1 and it still has this bug. It does not even compile itself (divtf3.c) with -Og.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 Richard Biener rguenth at gcc dot gnu.org changed: What|Removed |Added Status|ASSIGNED|RESOLVED Known to work||4.9.2 Resolution|--- |FIXED Target Milestone|--- |4.9.2 --- Comment #8 from Richard Biener rguenth at gcc dot gnu.org --- Fixed for 4.9.2.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #9 from Richard Biener rguenth at gcc dot gnu.org --- Author: rguenth Date: Thu Jul 17 07:53:16 2014 New Revision: 212741 URL: https://gcc.gnu.org/viewcvs?rev=212741root=gccview=rev Log: 2014-07-17 Richard Biener rguent...@suse.de Backport from mainline 2014-07-14 Richard Biener rguent...@suse.de PR tree-optimization/61779 * tree-ssa-copy.c (copy_prop_visit_cond_stmt): Always try simplifying a condition. * gcc.dg/tree-ssa/ssa-copyprop-2.c: New testcase. Added: branches/gcc-4_9-branch/gcc/testsuite/gcc.dg/tree-ssa/ssa-copyprop-2.c Modified: branches/gcc-4_9-branch/gcc/ChangeLog branches/gcc-4_9-branch/gcc/testsuite/ChangeLog branches/gcc-4_9-branch/gcc/tree-ssa-copy.c
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 Richard Biener rguenth at gcc dot gnu.org changed: What|Removed |Added Known to work||4.10.0 Known to fail||4.8.3, 4.9.1 --- Comment #4 from Richard Biener rguenth at gcc dot gnu.org --- Fixed for 4.10 sofar.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #5 from Vittorio Zecca zeccav at gmail dot com --- I just applied your fix and now gcc compiles succesfully with -Og.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #6 from rguenther at suse dot de rguenther at suse dot de --- On Tue, 15 Jul 2014, zeccav at gmail dot com wrote: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #5 from Vittorio Zecca zeccav at gmail dot com --- I just applied your fix and now gcc compiles succesfully with -Og. Thanks for the feedback on -Og btw - it hasn't seen very much testing coverage yet. Probably because the advertised fast compile-time is still much slower than with -O0.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779
--- Comment #7 from Vittorio Zecca zeccav at gmail dot com ---
I forgot to mention that my code fragment comes from
#include sys/sdt.h
void
f(void)
{
for (;;)
_SDT_PROBE(0, 0, 1,(0));
}
Maybe you can find intelligent ways to exercise this code and find
more -Og bugs?
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779
Richard Biener rguenth at gcc dot gnu.org changed:
What|Removed |Added
Status|UNCONFIRMED |ASSIGNED
Last reconfirmed||2014-07-14
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot
gnu.org
Ever confirmed|0 |1
--- Comment #2 from Richard Biener rguenth at gcc dot gnu.org ---
f ()
{
int iftmp.0_1;
bb 2:
bb 3:
bb 4:
# iftmp.0_1 = PHI 1(3)
__asm__ __volatile__(.pushsection .note.stapsdt,?,note
.4byte 992f-991f,994f-993f,3
.asciz %n0@%1
: : _SDT_S1 n iftmp.0_1, _SDT_A1 nor 0);
goto bb 3;
Huh. At -O0 we have the constant 1 propagated. From folding builtins
we get
_7 = 0;
if (_7 == 0)
goto bb 5;
else
goto bb 4;
bb 4:
bb 5:
# iftmp.0_1 = PHI 1(3), -1(4)
and copyprop then produces
bb 4:
# iftmp.0_1 = PHI 1(3)
because copyprop does
Visiting statement:
if (_7 == 0)
No interesting values produced.
Adding Destination of edge (3 - 5) to worklist
Adding Destination of edge (3 - 4) to worklist
err. Since copyprop also copy-propagates constants copy_prop_visit_cond_stmt
should try harder.
Mine.
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #3 from Richard Biener rguenth at gcc dot gnu.org --- Author: rguenth Date: Mon Jul 14 13:52:38 2014 New Revision: 212521 URL: https://gcc.gnu.org/viewcvs?rev=212521root=gccview=rev Log: 2014-07-14 Richard Biener rguent...@suse.de PR tree-optimization/61779 * tree-ssa-copy.c (copy_prop_visit_cond_stmt): Always try simplifying a condition. * gcc.dg/tree-ssa/ssa-copyprop-2.c: New testcase. Added: trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-copyprop-2.c Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-ssa-copy.c
[Bug c/61779] gcc -Og fails with impossible constraint on legal C code
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61779 --- Comment #1 from Vittorio Zecca zeccav at gmail dot com --- I forgot to say that gcc 4.9.0 fails but compiles correctly on gcc 4.8.3.
