Fix a QoI bug with overloaded operators inside macros.

We were failing to set source locations and ranges in isUnusedResultAWarning
for CXXOperatorCallExprs, leading to an "expression result unused" warning
with absolutely no context if the expression was inside a macro.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140036 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index 8beecc0856cf8b4e3d696b5ae9236bd85a130fc1..7983d61f041e36df85b4ed1402d6dc0cb03aa86a 100644 (file)
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -1631,8 +1631,11 @@ bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1,
     // DiagnoseUnusedComparison should be as well.
     const CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(this);
     if (Op->getOperator() == OO_EqualEqual ||
-        Op->getOperator() == OO_ExclaimEqual)
+        Op->getOperator() == OO_ExclaimEqual) {
+      Loc = Op->getOperatorLoc();
+      R1 = Op->getSourceRange();
       return true;
+    }
 
     // Fallthrough for generic call handling.
   }

diff --git a/test/SemaCXX/warn-unused-value.cpp b/test/SemaCXX/warn-unused-value.cpp
index 775c3cf01f243a6cd76fdfdd4c296432bd7a6218..80298ec6664a8820f70a41c17e7ab7591dc40601 100644 (file)
--- a/test/SemaCXX/warn-unused-value.cpp
+++ b/test/SemaCXX/warn-unused-value.cpp
@@ -15,3 +15,18 @@ namespace test0 {
     box->j;
   }
 }
+
+namespace test1 {
+struct Foo {
+  int i;
+  bool operator==(const Foo& rhs) {
+    return i == rhs.i;
+  }
+};
+
+#define NOP(x) (x)
+void b(Foo f1, Foo f2) {
+  NOP(f1 == f2);  // expected-warning {{expression result unused}}
+}
+#undef NOP
+}