[PATCH] D41478: [analyzer] Fix zero-initialization of stack VLAs under ARC.

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This revision was automatically updated to reflect the committed changes.
Closed by commit rC321290: [analyzer] Fix zero-initialization of stack VLAs under ObjC ARC. (authored by dergachev, committed by ).

Repository:
  rC Clang

https://reviews.llvm.org/D41478

Files:
  lib/StaticAnalyzer/Core/RegionStore.cpp
  test/Analysis/arc-zero-init.m


Index: test/Analysis/arc-zero-init.m
===================================================================
--- test/Analysis/arc-zero-init.m
+++ test/Analysis/arc-zero-init.m
@@ -0,0 +1,46 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core -verify %s
+// RUN: %clang_analyze_cc1 -analyzer-checker=core -verify -fobjc-arc %s
+
+#if __has_feature(objc_arc)
+// expected-no-diagnostics
+#endif
+
+ at interface SomeClass
+ at end
+
+void simpleStrongPointerValue() {
+  SomeClass *x;
+  if (x) {}
+#if !__has_feature(objc_arc)
+// expected-warning at -2{{Branch condition evaluates to a garbage value}}
+#endif
+}
+
+void simpleArray() {
+  SomeClass *vlaArray[5];
+
+  if (vlaArray[0]) {}
+#if !__has_feature(objc_arc)
+// expected-warning at -2{{Branch condition evaluates to a garbage value}}
+#endif
+}
+
+void variableLengthArray() {
+   int count = 1;
+   SomeClass * vlaArray[count];
+
+   if (vlaArray[0]) {}
+#if !__has_feature(objc_arc)
+  // expected-warning at -2{{Branch condition evaluates to a garbage value}}
+#endif
+}
+
+void variableLengthArrayWithExplicitStrongAttribute() {
+   int count = 1;
+   __attribute__((objc_ownership(strong))) SomeClass * vlaArray[count];
+
+   if (vlaArray[0]) {}
+#if !__has_feature(objc_arc)
+  // expected-warning at -2{{Branch condition evaluates to a garbage value}}
+#endif
+}
Index: lib/StaticAnalyzer/Core/RegionStore.cpp
===================================================================
--- lib/StaticAnalyzer/Core/RegionStore.cpp
+++ lib/StaticAnalyzer/Core/RegionStore.cpp
@@ -2132,9 +2132,10 @@
       NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
   }
 
-  // If the init list is shorter than the array length, set the
-  // array default value.
-  if (Size.hasValue() && i < Size.getValue())
+  // If the init list is shorter than the array length (or the array has
+  // variable length), set the array default value. Values that are already set
+  // are not overwritten.
+  if (!Size.hasValue() || i < Size.getValue())
     NewB = setImplicitDefaultValue(NewB, R, ElementTy);
 
   return NewB;


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