https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121380
Bug ID: 121380
Summary: ice with -O1 -fexceptions -favoid-store-forwarding
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
For this C code:
int selected_connection;
char string2num_sn[];
void *memcpy(void *, void *, long);
char string2num() {
string2num_sn[1] = 0;
string2num_sn[0] = string2num();
memcpy(&selected_connection, string2num_sn, 8);
}
compiled by recent gcc, does this:
$ ~/gcc/results.20250729.asan.ubsan/bin/gcc -c -w -freport-bug -O1
-fexceptions -favoid-store-forwarding bug1113b.c
$ ~/gcc/results.20250730.asan.ubsan/bin/gcc -c -w -freport-bug -O1
-fexceptions -favoid-store-forwarding bug1113b.c
during RTL pass: avoid_store_forwarding
bug1113b.c: In function ‘string2num’:
bug1113b.c:8:1: internal compiler error: Segmentation fault
8 | }
| ^
0x1ec51ce ???
/home/dcb42/gcc/working/gcc/../../trunk/gcc/diagnostic-global-context.cc:534
0xc34f79 ???
/home/dcb42/gcc/working/gcc/../../trunk/gcc/toplev.cc:323
0xc274ae is_constant<long>
../../trunk/gcc/poly-int.h:576
0xc274ae is_store_forwarding
/home/dcb42/gcc/working/gcc/../../trunk/gcc/avoid-store-forwarding.cc:152
$ ~/gcc/results.20250729.asan.ubsan/bin/gcc -v 2>&1 | grep exp
gcc version 16.0.0 20250729 (experimental) (b87d6ae3988e9d31)
$ ~/gcc/results.20250730.asan.ubsan/bin/gcc -v 2>&1 | grep exp
gcc version 16.0.0 20250730 (experimental) (d7cd6b0df54a29e2)
$
$ git log b87d6ae3988e9d31..d7cd6b0df54a29e2 | grep -c "^commit"
58
$
