[analyzer] Fix realloc related bug in the malloc checker.

When reallocation of a non-allocated (not owned) symbol fails do not
expect it to be freed.

llvm-svn: 162533

1 files changed, 14 insertions, 5 deletions

diff --git a/clang/test/Analysis/malloc.c b/clang/test/Analysis/malloc.c
index e3d92d9ad67..e7368af3f55 100644
--- a/clang/test/Analysis/malloc.c
+++ b/clang/test/Analysis/malloc.c
@@ -1000,17 +1000,26 @@ void freeButNoMalloc(int *p, int x){
 }
 
 struct HasPtr {
-  int *p;
+  char *p;
 };
 
-int* reallocButNoMalloc(struct HasPtr *a, int c, int size) {
+char* reallocButNoMalloc(struct HasPtr *a, int c, int size) {
   int *s;
-  a->p = (int *)realloc(a->p, size);
-  if (a->p == 0)
-    return 0; // expected-warning{{Memory is never released; potential leak}}
+  char *b = realloc(a->p, size);
+  char *m = realloc(a->p, size); // expected-warning {{Attempt to free released memory}}
   return a->p;
 }
 
+// We should not warn in this case since the caller will presumably free a->p in all cases.
+int reallocButNoMallocPR13674(struct HasPtr *a, int c, int size) {
+  int *s;
+  char *b = realloc(a->p, size);
+  if (b == 0)
+    return -1;
+  a->p = b;
+  return 0;
+}
+
 // ----------------------------------------------------------------------------
 // False negatives.