More tests for uninitialized variable warnings

From-SVN: r25770

gcc/testsuite/gcc.dg/uninit-5.c

+/* Spurious uninitialized-variable warnings.
+   These cases are documented as not working in the gcc manual. */
+
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+extern void use(int);
+extern void foo(void);
+
+void
+func1(int cond)
+{
+    int x;  /* { dg-bogus "x" "uninitialized variable warning" { xfail *-*-* } } */
+
+    if(cond)
+	x = 1;
+
+    foo();
+
+    if(cond)
+	use(x);
+}
+
+void
+func2 (int cond)
+{
+    int x;  /* { dg-bogus "x" "uninitialized variable warning" { xfail *-*-* } } */
+    int flag = 0;
+
+    if(cond)
+    {
+	x = 1;
+	flag = 1;
+    }
+
+    foo();
+
+    if(flag)
+	use(x);
+}

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

+/* Spurious uninitialized variable warnings.
+   This one inspired by java/class.c:build_utf8_ref.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+#include <stddef.h>
+
+struct tree
+{
+    struct tree *car;
+    struct tree *cdr;
+    int type, data;
+};
+
+extern void *malloc(size_t);
+
+#define INTEGER_T 1
+#define PTR_T	  2
+
+#define APPEND(TREE, LAST, TYPE, VALUE)				\
+do {								\
+     struct tree *tmp = malloc (sizeof (struct tree));		\
+     tmp->car = 0; tmp->cdr = 0; tmp->type = TYPE;		\
+     tmp->data = VALUE;						\
+     if (TREE->car)						\
+	 LAST->cdr = tmp;					\
+     else							\
+	 TREE->car = tmp;					\
+     LAST = tmp;						\
+} while(0)
+ 
+struct tree *
+make_something(int a, int b, int c)
+{
+    struct tree *rv;
+    struct tree *field;  /* { dg-bogus "field" "uninitialized variable warning" { xfail *-*-* } } */
+
+    rv = malloc (sizeof (struct tree));
+    rv->car = 0;
+
+    APPEND(rv, field, INTEGER_T, a);
+    APPEND(rv, field, PTR_T, b);
+    APPEND(rv, field, INTEGER_T, c);
+
+    return rv;
+}

gcc/testsuite/gcc.dg/uninit-8.c

+/* Uninitialized variable warning tests...
+   Inspired by part of optabs.c:expand_binop.
+   May be the same as uninit-1.c.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+#include <limits.h>
+
+void
+add_bignums (int *out, int *x, int *y)
+{
+    int p, sum;
+    int carry; /* { dg-bogus "carry" "uninitialized variable warning" { xfail *-*-* } } */
+
+    p = 0;
+    for (; *x; x++, y++, out++, p++)
+    {
+	if (p)
+	    sum = *x + *y + carry;
+	else
+	    sum = *x + *y;
+
+	if (sum < 0)
+	{
+	    carry = 1;
+	    sum -= INT_MAX;
+	}
+	else
+	    carry = 0;
+    }
+}

gcc/testsuite/gcc.dg/uninit-9.c

+/* Spurious uninitialized variable warnings.  Slight variant on the
+   documented case, inspired by reg-stack.c:record_asm_reg_life.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+struct foo
+{
+    int type;
+    struct foo *car;
+    struct foo *cdr;
+    char *data;
+    int data2;
+};
+
+extern void use(struct foo *);
+
+#define CLOBBER 6
+#define PARALLEL 3
+
+void
+func(struct foo *list, int count)
+{
+    int n_clobbers = 0;
+    int i;
+    struct foo **clob_list;   /* { dg-bogus "clob_list" "uninitialized variable warning" { xfail *-*-* } } */
+
+    if(list[0].type == PARALLEL)
+    {
+	clob_list = alloca(count * sizeof(struct foo *));
+	
+	for(i = 1; i < count; i++)
+	{
+	    if(list[i].type == CLOBBER)
+		clob_list[n_clobbers++] = &list[i];
+	}
+    }
+
+    for(i = 0; i < n_clobbers; i++)
+	use(clob_list[i]);
+}