[RecursiveASTVisitor] Fix post-order traversal of UnaryOperator

Reviewers: aaron.ballman, klimek, doug.gregor, teemperor, rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D26742

llvm-svn: 288923

2 files changed, 9 insertions, 3 deletions

diff --git a/clang/include/clang/AST/RecursiveASTVisitor.h b/clang/include/clang/AST/RecursiveASTVisitor.h
index d08d47744ae..d3a651643a2 100644
--- a/clang/include/clang/AST/RecursiveASTVisitor.h
+++ b/clang/include/clang/AST/RecursiveASTVisitor.h
@@ -357,7 +357,8 @@ public:
 #define OPERATOR(NAME)                                                         \
   bool TraverseUnary##NAME(UnaryOperator *S,                                   \
                            DataRecursionQueue *Queue = nullptr) {              \
-    TRY_TO(WalkUpFromUnary##NAME(S));                                          \
+    if (!getDerived().shouldTraversePostOrder())                               \
+      TRY_TO(WalkUpFromUnary##NAME(S));                                        \
     TRY_TO_TRAVERSE_OR_ENQUEUE_STMT(S->getSubExpr());                          \
     return true;                                                               \
   }                                                                            \
diff --git a/clang/unittests/AST/PostOrderASTVisitor.cpp b/clang/unittests/AST/PostOrderASTVisitor.cpp
index 012f63a48ad..ee17f14bd10 100644
--- a/clang/unittests/AST/PostOrderASTVisitor.cpp
+++ b/clang/unittests/AST/PostOrderASTVisitor.cpp
@@ -34,6 +34,11 @@ namespace {
 
     bool shouldTraversePostOrder() const { return VisitPostOrder; }
 
+    bool VisitUnaryOperator(UnaryOperator *Op) {
+      VisitedNodes.push_back(Op->getOpcodeStr(Op->getOpcode()));
+      return true;
+    }
+
     bool VisitBinaryOperator(BinaryOperator *Op) {
       VisitedNodes.push_back(Op->getOpcodeStr());
       return true;
@@ -76,7 +81,7 @@ TEST(RecursiveASTVisitor, PostOrderTraversal) {
   auto ASTUnit = tooling::buildASTFromCode(
     "class A {"
     "  class B {"
-    "    int foo() { while(4) { int i = 9; } return (1 + 3) + 2; }"
+    "    int foo() { while(4) { int i = 9; int j = -i; } return (1 + 3) + 2; }"
     "  };"
     "};"
   );
@@ -87,7 +92,7 @@ TEST(RecursiveASTVisitor, PostOrderTraversal) {
   Visitor.TraverseTranslationUnitDecl(TU);
 
   std::vector<std::string> expected = {
-    "4", "9", "i", "1", "3", "+", "2", "+", "return", "A::B::foo", "A::B", "A"
+    "4", "9", "i", "-", "j", "1", "3", "+", "2", "+", "return", "A::B::foo", "A::B", "A"
   };
   // Compare the list of actually visited nodes
   // with the expected list of visited nodes.