[analyzer] Fix handling of "empty" structs with base classes
Summary:
RegionStoreManager had an optimization which replaces references to empty
structs with UnknownVal. Unfortunately, this check didn't take into account
possible field members in base classes.
To address this, I changed this test to "is empty and has no base classes". I
don't consider it worth the trouble to go through base classes and check if all
of them are empty.
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1547
llvm-svn: 189590
diff --git a/clang/test/Analysis/array-struct-region.cpp b/clang/test/Analysis/array-struct-region.cpp
index 12ae5d3..a776d7d 100644
--- a/clang/test/Analysis/array-struct-region.cpp
+++ b/clang/test/Analysis/array-struct-region.cpp
@@ -173,4 +173,27 @@
clang_analyzer_eval(getConstrainedFieldRefOp(getS()) == 42); // expected-warning{{TRUE}}
}
+namespace EmptyClass {
+ struct Base {
+ int& x;
+
+ Base(int& x) : x(x) {}
+ };
+
+ struct Derived : public Base {
+ Derived(int& x) : Base(x) {}
+
+ void operator=(int a) { x = a; }
+ };
+
+ Derived ref(int& a) { return Derived(a); }
+
+ // There used to be a warning here, because analyzer treated Derived as empty.
+ int test() {
+ int a;
+ ref(a) = 42;
+ return a; // no warning
+ }
+}
+
#endif