https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84132
Bug ID: 84132
Summary: tree-data-ref.c:3938: poor coding ?
Product: gcc
Version: 8.0
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++ source code:
struct g {
char b;
unsigned char *d[];
} e;
unsigned char f;
void i() {
for (int h;; h++) {
unsigned a = h;
for (int c = 0; c < 256; c += 6)
for (int h = c; h < c + 6; h++)
e.d[h + a] = &f;
}
}
with recent versions of trunk g++ and compiler flag -O3, I get
during GIMPLE pass: unrolljam
bug416-min.cc: In function ‘void i()’:
bug416-min.cc:6:6: internal compiler error: Illegal instruction
void i() {
^
0x10e68bf crash_signal
../../trunk/gcc/toplev.c:325
0x7da22f gcd_of_steps_may_divide_p
../../trunk/gcc/tree-data-ref.c:3938
0x7da22f analyze_miv_subscript
../../trunk/gcc/tree-data-ref.c:3982
The source code at trunk/gcc/tree-data-ref.c:3938 is
return val % cd == 0;
The problem seems to exist between revision 257009 and 257076.
