https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79768
Bug ID: 79768
Summary: `-Wmaybe-uninitialized' false positive with
optimisation
Product: gcc
Version: 5.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: caspervector at gmail dot com
Target Milestone: ---
The following source file (here called `gcc_bug.c') triggers
`-Wmaybe-uninitialized' when compiled with `-Os', `-O1' or stronger
optimisation, plus `-Wall':
------------------------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
static int mk (int **a, int **b, int **c) {
if (!(*a = malloc (sizeof (int)))) goto a_err;
if (!(*b = malloc (sizeof (int)))) goto b_err;
if (!(*c = malloc (sizeof (int)))) goto c_err;
return 1; c_err:
free (*b); b_err:
free (*a); a_err:
return 0;
}
static void fin (int *a, int *b, int *c) {
free (c);
free (b);
free (a);
}
int main (void) {
int *a, *b, *c, x, flag = mk (&a, &b, &c);
while ((x = getchar ()) != -1) {
if (flag) switch (x) {
case 0:
break;
default:
goto retn;
} else if (x) goto retn;
}
retn:
if (flag) fin (a, b, c);
return 0;
}
------------------------------------------------------------------------
