gcc version 4.2.0 20060121
With optimzation the following code skips the last loop iteration:
#include <stdio.h>
int main(void)
{
int bits = 25;
while (bits) {
printf("bits=%d\n",bits);
if (bits >= 8) {
bits -= 8;
} else {
bits = 0;
}
}
return 0;
}
[EMAIL PROTECTED]:~/pg/test$ ~/gcc/42/bin/gcc ip2.c
[EMAIL PROTECTED]:~/pg/test$ ./a.out
bits=25
bits=17
bits=9
bits=1
[EMAIL PROTECTED]:~/pg/test$ ~/gcc/42/bin/gcc -O ip2.c
[EMAIL PROTECTED]:~/pg/test$ ./a.out
bits=25
bits=17
bits=9
[EMAIL PROTECTED]:~/pg/test$
--
Summary: with optimization integer math fails
Product: gcc
Version: 4.2.0
Status: UNCONFIRMED
Severity: critical
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: jurka at ejurka dot com
GCC build triplet: i686-pc-linux-gnu
GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25985
