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[Bug middle-end/58419] New: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode
- From: "su at cs dot ucdavis.edu" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Fri, 13 Sep 2013 23:18:56 +0000
- Subject: [Bug middle-end/58419] New: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode
- Auto-submitted: auto-generated
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58419
Bug ID: 58419
Summary: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: su at cs dot ucdavis.edu
The current gcc trunk mis-compiles the following code on x86_64-linux at -O3 in
32-bit mode.
This is a regression from 4.8.x.
$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure
--enable-languages=c,c++,objc,obj-c++,fortran,lto
--with-gmp=/usr/local/gcc-trunk --with-mpfr=/usr/local/gcc-trunk
--with-mpc=/usr/local/gcc-trunk --with-cloog=/usr/local/gcc-trunk
--prefix=/usr/local/gcc-trunk
Thread model: posix
gcc version 4.9.0 20130913 (experimental) [trunk revision 202556] (GCC)
$ gcc-trunk -m32 -O2 small.c
$ a.out
0
$ gcc-4.8 -m32 -O3 small.c
$ a.out
0
$ gcc-trunk -m64 -O3 small.c
$ a.out
0
$ gcc-trunk -m32 -O3 small.c
$ a.out
Segmentation fault (core dumped)
$
-----------------------------------
int printf(const char *, ...);
int a, g, i, k, *p;
char b, e;
short c, h;
static short *d = &c;
char
foo (int p1, int p2)
{
return p1 - p2;
}
int
bar ()
{
short *q = &c;
*q = 1;
*p = 0;
return 0;
}
int
main ()
{
for (b = -22; b >= -29; b--)
{
short *l = &h;
char *m = &e;
*l = a;
g = foo (*m = k && *d, 1 > i) || bar ();
}
printf("0\n");
return 0;
}