https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113555
Bug ID: 113555
Summary: Yet another failure in verify_ssa
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
Today's gcc trunk says:
$ ~/gcc/results.20240123.asan.ubsan/bin/gcc -c -O3 -w bug1000.c
$ ~/gcc/results.20240123.asan.ubsan/bin/gcc -c -O3 -w -march=znver3 bug1000.c
bug1000.c: In function ‘net_roa_check_ip4_trie_tab’:
bug1000.c:20:6: error: definition in block 4 does not dominate use in block 5
20 | void net_roa_check_ip4_trie_tab() {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
for SSA_NAME: vect__14.32_111 in statement:
vect__14.32_112 = PHI <vect__14.32_111(5)>
PHI argument
vect__14.32_111
for PHI node
vect__14.32_112 = PHI <vect__14.32_111(5)>
during GIMPLE pass: vect
bug1000.c:20:6: internal compiler error: verify_ssa failed
Reduced source code is
int ip4_getbit_a, ip4_getbit_pos, ip4_clrbit_pos;
void ip4_clrbit(int *a) { *a &= ip4_clrbit_pos; }
typedef struct {
char pxlen;
int prefix
} net_addr_ip4;
void fib_get_chain();
int trie_match_longest_ip4();
int trie_match_next_longest_ip4(net_addr_ip4 *n) {
int __trans_tmp_1;
while (n->pxlen) {
n->pxlen--;
ip4_clrbit(&n->prefix);
__trans_tmp_1 = ip4_getbit_a >> ip4_getbit_pos;
if (__trans_tmp_1)
return 1;
}
return 0;
}
void net_roa_check_ip4_trie_tab() {
net_addr_ip4 px0;
for (int _n = trie_match_longest_ip4(&px0); _n;
_n = trie_match_next_longest_ip4(&px0))
fib_get_chain();
}
The bug seems to have existed since at least 20231227.
On a side note, 1000 bug reports and enhancement requests in 11 years.
