re PR middle-end/40943 (Uninitialized warning is missed when dereferencing uninitialized pointers)

	PR middle-end/40943
	* tree-ssa.c (warn_uninitialized_var): Even on LHS warn for
	operand of INDIRECT_REF.

	* gcc.dg/uninit-6.c: Re-add XFAIL.
	* gcc.dg/uninit-6-O0.c: Likewise.
	* gcc.dg/uninit-pr40943.c: New test.

From-SVN: r150379

gcc/ChangeLog

+2009-08-03  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/40943
+	* tree-ssa.c (warn_uninitialized_var): Even on LHS warn for
+	operand of INDIRECT_REF.
+
 2009-08-03  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/alpha/alpha.c (alpha_legitimate_constant_p): Reject CONST

gcc/testsuite/ChangeLog

+2009-08-03  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/40943
+	* gcc.dg/uninit-6.c: Re-add XFAIL.
+	* gcc.dg/uninit-6-O0.c: Likewise.
+	* gcc.dg/uninit-pr40943.c: New test.
+
 2009-08-03  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>
 
 	PR testsuite/40858

gcc/testsuite/gcc.dg/uninit-6-O0.c

@@ -39,7 +39,7 @@ make_something(int a, int b, int c)
     rv = malloc (sizeof (struct tree));
     rv->car = 0;
 
-    APPEND(rv, field, INTEGER_T, a);  /* { dg-bogus "field" "uninitialized variable warning" } */
+    APPEND(rv, field, INTEGER_T, a);  /* { dg-bogus "field" "uninitialized variable warning" { xfail *-*-* } } */
     APPEND(rv, field, PTR_T, b);
     APPEND(rv, field, INTEGER_T, c);
 

gcc/testsuite/gcc.dg/uninit-6.c

@@ -39,7 +39,7 @@ make_something(int a, int b, int c)
     rv = malloc (sizeof (struct tree));
     rv->car = 0;
 
-    APPEND(rv, field, INTEGER_T, a);  /* { dg-bogus "field" "uninitialized variable warning" } */
+    APPEND(rv, field, INTEGER_T, a);  /* { dg-bogus "field" "uninitialized variable warning" { xfail *-*-* } } */
     APPEND(rv, field, PTR_T, b);
     APPEND(rv, field, INTEGER_T, c);
 

gcc/testsuite/gcc.dg/uninit-pr40943.c

+/* PR middle-end/40943 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wuninitialized" } */
+
+void
+foo (void)
+{
+  int *p;
+  *p = 3;	/* { dg-warning "is used uninitialized" } */
+}

gcc/tree-ssa.c

@@ -1265,7 +1265,12 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_)
 
   /* We do not care about LHS.  */
   if (wi->is_lhs)
-    return NULL_TREE;
+    {
+      /* Except for operands of INDIRECT_REF.  */
+      if (!INDIRECT_REF_P (t))
+	return NULL_TREE;
+      t = TREE_OPERAND (t, 0);
+    }
 
   switch (TREE_CODE (t))
     {