-Warc-repeated-use-of-weak: Don't warn on a single read followed by writes.
This is a "safe" pattern, or at least one that cannot be helped by using
a strong local variable. However, if the single read is within a loop,
it should /always/ be treated as potentially dangerous.
<rdar://problem/12437490>
llvm-svn: 165719
diff --git a/clang/test/SemaObjC/arc-repeated-weak.mm b/clang/test/SemaObjC/arc-repeated-weak.mm
index ca13e20..a59f435 100644
--- a/clang/test/SemaObjC/arc-repeated-weak.mm
+++ b/clang/test/SemaObjC/arc-repeated-weak.mm
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-arc -fblocks -Wno-objc-root-class -Warc-repeated-use-of-weak -verify %s
+// RUN: %clang_cc1 -fsyntax-only -fobjc-runtime-has-weak -fobjc-arc -fblocks -Wno-objc-root-class -std=c++11 -Warc-repeated-use-of-weak -verify %s
@interface Test {
@public
@@ -181,6 +181,70 @@
}
}
+void assignAfterRead(Test *a) {
+ // Special exception for a single read before any writes.
+ if (!a.weakProp) // no-warning
+ a.weakProp = get(); // no-warning
+}
+
+void readOnceWriteMany(Test *a) {
+ if (!a.weakProp) { // no-warning
+ a.weakProp = get(); // no-warning
+ a.weakProp = get(); // no-warning
+ }
+}
+
+void readOnceAfterWrite(Test *a) {
+ a.weakProp = get(); // expected-note{{also accessed here}}
+ if (!a.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ a.weakProp = get(); // expected-note{{also accessed here}}
+ }
+}
+
+void readOnceWriteManyLoops(Test *a, Test *b, Test *c, Test *d, Test *e) {
+ while (condition()) {
+ if (!a.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ a.weakProp = get(); // expected-note{{also accessed here}}
+ a.weakProp = get(); // expected-note{{also accessed here}}
+ }
+ }
+
+ do {
+ if (!b.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ b.weakProp = get(); // expected-note{{also accessed here}}
+ b.weakProp = get(); // expected-note{{also accessed here}}
+ }
+ } while (condition());
+
+ for (id x = get(); x; x = get()) {
+ if (!c.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ c.weakProp = get(); // expected-note{{also accessed here}}
+ c.weakProp = get(); // expected-note{{also accessed here}}
+ }
+ }
+
+ for (id x in get()) {
+ if (!d.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ d.weakProp = get(); // expected-note{{also accessed here}}
+ d.weakProp = get(); // expected-note{{also accessed here}}
+ }
+ }
+
+ int array[] = { 1, 2, 3 };
+ for (int i : array) {
+ if (!e.weakProp) { // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ e.weakProp = get(); // expected-note{{also accessed here}}
+ e.weakProp = get(); // expected-note{{also accessed here}}
+ }
+ }
+}
+
+void readOnlyLoop(Test *a) {
+ while (condition()) {
+ use(a.weakProp); // expected-warning{{weak property 'weakProp' is accessed multiple times in this function}}
+ }
+}
+
@interface Test (Methods)
@end
@@ -248,11 +312,6 @@
// Most of these would require flow-sensitive analysis to silence correctly.
-void assignAfterRead(Test *a) {
- if (!a.weakProp) // expected-warning{{weak property 'weakProp' is accessed multiple times}}
- a.weakProp = get(); // expected-note{{also accessed here}}
-}
-
void assignNil(Test *a) {
if (condition())
a.weakProp = nil; // expected-note{{also accessed here}}