https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81083
Bug ID: 81083
Summary: [7 Regression] ICE: Unable to coalesce ssa_names 4 and
13 which are marked as MUST COALESCE
Product: gcc
Version: 7.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: k at rhe dot jp
Target Milestone: ---
The function below triggers an internal compiler error with GCC 7.1.1 and
trunk.
$ cat test.c
void a(int arg) {
extern struct { int x; } obj;
setjmp();
obj.x = arg;
arg = arg;
if (obj.x)
func();
if (obj.x)
func();
}
$ gcc -O2 -w -c test.c
Unable to coalesce ssa_names 4 and 13 which are marked as MUST COALESCE.
arg_4(ab) and arg_13(ab)
during RTL pass: expand
test.c: In function ‘a’:
test.c:1:6: internal compiler error: SSA corruption
void a(int arg) {
^
0xd4f149 fail_abnormal_edge_coalesce
../.././gcc/tree-ssa-coalesce.c:1010
0xd4f149 coalesce_partitions
../.././gcc/tree-ssa-coalesce.c:1399
0xd4f149 coalesce_ssa_name()
../.././gcc/tree-ssa-coalesce.c:1886
0xce9958 remove_ssa_form
../.././gcc/tree-outof-ssa.c:948
0xce9958 rewrite_out_of_ssa(ssaexpand*)
../.././gcc/tree-outof-ssa.c:1172
0x862c50 execute
../.././gcc/cfgexpand.c:6161
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
