https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78162
Bug ID: 78162 Summary: ICE on invalid code at -Os and above on x86_64-linux-gnu: Segmentation fault Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu Target Milestone: --- This is a regression from 6.2.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 20161030 (experimental) [trunk revision 241684] (GCC) $ $ gcc-trunk -O1 -c small.c $ gcc-6.2 -Os -c small.c $ $ gcc-trunk -Os -c small.c small.c: In function ‘fn1’: small.c:3:6: internal compiler error: Segmentation fault void fn1() ^~~ 0xbedacf crash_signal ../../gcc-source-trunk/gcc/toplev.c:338 0x12dfed1 vec<gimple*, va_heap, vl_embed>::operator[](unsigned int) ../../gcc-source-trunk/gcc/vec.h:732 0x12dfed1 vec<gimple*, va_heap, vl_ptr>::operator[](unsigned int) ../../gcc-source-trunk/gcc/vec.h:1216 0x12dfed1 get_alias_type_for_stmts ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:941 0x12dfed1 output_merged_store ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:1129 0x12dfed1 output_merged_stores ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:1213 0x12dfed1 terminate_and_process_chain ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:1251 0x12dfed1 terminate_and_release_chain ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:833 0x12e0d38 terminate_all_aliasing_chains ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:811 0x12e120e execute ../../gcc-source-trunk/gcc/gimple-ssa-store-merging.c:1456 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. $ ------------------------------- int a, b[1][2]; void fn1() { for (a = 0; a < 2; a++) b[-1][a] = 0; }