http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46755
--- Comment #9 from H.J. Lu <hjl.tools at gmail dot com> 2011-01-02 23:12:46 UTC --- (In reply to comment #8) > 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) > { > } > } This is caused by revision 164431: http://gcc.gnu.org/ml/gcc-cvs/2010-09/msg00727.html
