https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77544
Bug ID: 77544
Summary: [Regression 6/7] segfault at -O0 - infinite loop in
simplification
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: babokin at gmail dot com
Target Milestone: ---
Created attachment 39594
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39594&action=edit
reproducer
> g++ -O0 -c func.cpp
g++: internal compiler error: Segmentation fault (program cc1plus)
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
Here's top of the stack when it fails (stack is huge):
#0 0x0000000000a37c59 in operand_equal_p (...) at
./svn/trunk/gcc/fold-const.c:2744
#1 0x0000000000a37e50 in operand_equal_p (...) at
./svn/trunk/gcc/fold-const.c:2750
#2 0x000000000115c676 in generic_simplify_MINUS_EXPR (...) at
generic-match.c:11785
#3 0x0000000001174bbe in generic_simplify (...) at generic-match.c:31249
#4 0x0000000000a47af3 in fold_binary_loc (...) at
./svn/trunk/gcc/fold-const.c:9161
#5 0x0000000000a52a0b in fold_build2_stat_loc (...) at
./svn/trunk/gcc/fold-const.c:12291
#6 0x0000000001138dc0 in generic_simplify_181 (...) at generic-match.c:6690
#7 0x000000000114c81b in generic_simplify_PLUS_EXPR (...) at
generic-match.c:11152
#8 0x0000000001174bde in generic_simplify (...) at generic-match.c:31245
#9 0x0000000000a47af3 in fold_binary_loc (...) at
./svn/trunk/gcc/fold-const.c:9161
#10 0x0000000000a52a0b in fold_build2_stat_loc (...) at
./svn/trunk/gcc/fold-const.c:12291
#11 0x0000000000a4a142 in fold_binary_loc (...) at
./svn/trunk/gcc/fold-const.c:9695
#12 0x0000000000a52a0b in fold_build2_stat_loc (...) at
./svn/trunk/gcc/fold-const.c:12291
#13 0x000000000115c762 in generic_simplify_MINUS_EXPR (...) at
generic-match.c:12390
It's reproducible with gcc6 and trunk. gcc5 works.
GCC build details:
> g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/users/ddd/gcc_20160909/bin/../libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /users/ddd/stability/svn/trunk/configure --with-arch=corei7
--with-cpu=corei7 --enable-clocale=gnu --enable-libmpx=yes --with-system-zlib
--enable-shared --with-demangler-in-ld --enable-cloog-backend=isl
--with-fpmath=sse --with-pkgversion=Revision=240038/svn-rev:240038/
--prefix=/users/ddd/stability/work/trunk/64/install
--enable-languages=c,c++,fortran,java,lto
Thread model: posix
gcc version 7.0.0 20160908 (experimental) (Revision=240038/svn-rev:240038/)
