https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71588
Bug ID: 71588 Summary: ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in execute_todo, at passes.c:2009 Product: gcc Version: 7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu Target Milestone: --- The following code causes an ICE when compiled with the current gcc trunk at -O2 and -O3on x86_64-linux-gnu in both 32-bit and 64-bit modes. It is a regression from 6.1.x. $ gcc-trunk -v Using built-in specs. COLLECT_GCC=gcc-trunk COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto --prefix=/usr/local/gcc-trunk --disable-bootstrap Thread model: posix gcc version 7.0.0 20160619 (experimental) [trunk revision 237580] (GCC) $ $ gcc-trunk -Os -c small.c $ gcc-6.1 -O2 -c small.c $ $ gcc-trunk -O2 -c small.c small.c: In function ‘foo’: small.c:7:7: internal compiler error: in execute_todo, at passes.c:2009 char *foo () ^~~ 0xafa57c execute_todo ../../gcc-source-trunk/gcc/passes.c:2009 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. $ ----------------------------------------------------------------- char *strcpy (char *, const char *) __attribute__ ((__pure__)); unsigned long strlen (const char *); void *malloc (unsigned long); char a; char *foo () { unsigned long b = strlen (&a); char *c = malloc (b); return strcpy (c, &a); }