[Bug tree-optimization/63748] [4.9/5 Regression] may be used uninitialized warning on variable definition with initializer

[uweigand at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63748

Ulrich Weigand <uweigand at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |uweigand at gcc dot gnu.org

--- Comment #2 from Ulrich Weigand <uweigand at gcc dot gnu.org> ---
Much simplified test case:

typedef struct __jmp_buf_tag jmp_buf;
extern int setjmp (jmp_buf *);
jmp_buf *alloc_jmp_buf ();
int foo (void *);

int
test (int op, int noside)
{
  void *argvec = 0;

  if (op)
    {
      jmp_buf *buf = alloc_jmp_buf ();
      setjmp (buf);

      if (noside)
        goto nosideret;

    do_call_it:

      if (noside)
        goto nosideret;

      return foo (argvec);
    }

  argvec = __builtin_alloca (1);
  goto do_call_it;

nosideret:
  return 1;
}

results in:

xxx.i: In function ‘test’:
xxx.i:14:16: error: ‘buf’ may be used uninitialized in this function
[-Werror=maybe-uninitialized]
       jmp_buf *buf = alloc_jmp_buf ();