[analyzer] teach analyzer about ObjC literals, thus trimming out a false positive with the malloc() checker involving

comparing literal addresses to nil.

Fixes <rdar://problem/10579586>

llvm-svn: 151602

1 files changed, 37 insertions, 0 deletions

diff --git a/clang/test/Analysis/malloc.m b/clang/test/Analysis/malloc.m
new file mode 100644
index 00000000000..6451dbc9839
--- /dev/null
+++ b/clang/test/Analysis/malloc.m
@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.Malloc -analyzer-store=region -verify %s
+#include "system-header-simulator-objc.h"
+
+@class NSString;
+typedef __typeof(sizeof(int)) size_t;
+void *malloc(size_t);
+void free(void *);
+
+// RDar10579586 - Test use of malloc() with Objective-C string literal as a
+// test condition.  Not really a malloc() issue, but this also exercises
+// the check that malloc() returns uninitialized memory.
+@interface RDar10579586
+struct rdar0579586_str {
+    char str_c;
+};
+@end
+
+void rdar10579586(char x);
+
+@implementation RDar10579586
++ (NSString *)foobar
+{
+    struct rdar0579586_str *buffer = ((void*)0);
+    NSString *error = ((void*)0);
+
+    if ((buffer = malloc(sizeof(struct rdar0579586_str))) == ((void*)0))
+        error = @"buffer allocation failure";
+
+    if (error != ((void*)0))
+        return error;
+
+    rdar10579586(buffer->str_c); // expected-warning {{Function call argument is an uninitialized value}}
+    free(buffer);
+    return ((void*)0);
+}
+@end
+