https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64327
--- Comment #4 from Vittorio Zecca <zeccav at gmail dot com> --- For your convenience I repeat here the reproducer: /* from gcc file fixopts.c */ /* must be compiled with -O2 */ /*gcc-5.1.0/gcc/rtlanal.c:4911:48: runtime error: shift exponent 4294967295 is too large for 64-bit type 'long unsigned int'*/ /*on source line "return nonzero & ((unsigned HOST_WIDE_INT) 1 << (bitwidth - 1))"*/ /* because unsigned int bitwidth is zero and bitwitdth-1 is 4294967295 on my x86-64 */ /* I did double check with: * bitwidth = GET_MODE_PRECISION (mode); * gcc_assert(bitwidth); */ /* the bug appears compiling fixopts.c crc32.c md5.c and many Fedora 21 kernel files*/ /* 66853 duplicato di 64327 */ int strcmp(const char *s1, const char *s2); int fixinc_mode; /* must be outside main for bug to appear */ int main (void) { const char *pz; if (strcmp (pz, "true") ) fixinc_mode = 0; }