http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46755
John Regehr <regehr at cs dot utah.edu> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |regehr at cs dot utah.edu --- Comment #8 from John Regehr <regehr at cs dot utah.edu> 2011-01-02 20:48:22 UTC --- Not sure if this is still useful, but here's a fairly small failure-inducing testcase for this bug for today's GCC. [reg...@gamow tmp437]$ current-gcc -O2 -c small.c small.c: In function 'func': small.c:32:1: internal compiler error: in calc_dfs_tree, at dominance.c:395 Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. [reg...@gamow tmp437]$ current-gcc -v Using built-in specs. COLLECT_GCC=current-gcc COLLECT_LTO_WRAPPER=/uusoc/exports/scratch/regehr/z/compiler-install/gcc-r168402-install/bin/../libexec/gcc/x86_64-unknown-linux-gnu/4.6.0/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/regehr/z/compiler-install/gcc-r168402-install --program-prefix=r168402- --enable-languages=c,c++ Thread model: posix gcc version 4.6.0 20110102 (experimental) (GCC) [reg...@gamow tmp437]$ cat small.c static int foo (int si1, short si2) { return ((si1 ^ si2) & ((si1 ^ (si1 ^ si2) & ~2147483647) - si2 ^ si2)) < 0 ? si1 : si1 - si2; } struct S0 { const unsigned f3:1; const unsigned f8:1; }; struct S0 g_111 = { 1 }; struct S0 g_139 = { 1 }; unsigned long int g_22; void safe (int); int func_42 (void); void func (void) { safe (foo (func_42 () != (g_139.f3 | g_111.f8), -1L)); for (g_22 = 0; g_22; g_22 = 1) { } }