http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49958
Summary: fold performs invalid association
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: [email protected]
ReportedBy: [email protected]
extern void abort (void);
int foo (int i, int j, int o, int m) { return i*o + 1 + j*m > 1; }
int main()
{
if (foo (- __INT_MAX__ - 1, -1, 1, 1))
abort ();
return 0;
}
abort()s with -fstrict-overflow even though there is no overflow
involved in INT_MIN + 1 - 1. But fold re-associates this to
INT_MIN - 1 + 1 which overflows (it does require the two multiplications
to trigger).
