https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104156
Bug ID: 104156
Summary: -fcompare-debug failure with -O3
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: cnsun at uwaterloo dot ca
Target Milestone: ---
$ gcc-trunk -fcompare-debug -O3 small.c
gcc-trunk: error: small.c: ‘-fcompare-debug’ failure (length)
$
$ cat small.c
short a, d;
int b, c;
static int e() {
int f = -2L, g = 9, h = 0;
for (; h < 2; h++)
if (a <= 5) {
g = 0;
if (c && a)
break;
if (c - 1)
goto i;
}
if (b) {
int *j[] = {&f};
if (d)
for (; f < 9; f++)
if (g)
for (; f; f++)
;
i:
while (f) {
a--;
break;
}
}
}
int main() { e(); }
$
$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/scratch/software/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/12.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /tmp/tmp.ahmEMGgtK2-gcc-builder/gcc/configure
--enable-languages=c,c++,lto --enable-checking-yes --enable-multiarch
--prefix=/scratch/software/gcc-trunk --disable-bootstrap
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 12.0.1 20220120 (experimental) [master -g30f2c22de] (GCC)
$
