Classes inside lambdas are local not nested.

If a lambda used as default argument in a method declaration contained
a local class, that class was incorrectly recognized as nested class.
In this case compiler tried to postpone parsing of this class until
the enclosing class is finished, which caused crashes in some cases.

This change fixes PR13987.

Differential Revision: http://reviews.llvm.org/D11006

llvm-svn: 242132

Author: spavloff

clang/lib/Parse/ParseDeclCXX.cpp

@@ -2815,16 +2815,10 @@ void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
         break;
       }
 
-      if ((S->getFlags() & Scope::FnScope)) {
-        // If we're in a function or function template declared in the
-        // body of a class, then this is a local class rather than a
-        // nested class.
-        const Scope *Parent = S->getParent();
-        if (Parent->isTemplateParamScope())
-          Parent = Parent->getParent();
-        if (Parent->isClassScope())
-          break;
-      }
+      if ((S->getFlags() & Scope::FnScope))
+        // If we're in a function or function template then this is a local
+        // class rather than a nested class.
+        break;
     }
   }
 

clang/test/SemaCXX/cxx1y-generic-lambdas.cpp

@@ -948,3 +948,41 @@ auto f(T x) {
 
 auto x = f(0)();
 }
+
+namespace PR13987 {
+class Enclosing {
+  void Method(char c = []()->char {
+    int d = [](auto x)->int {
+        struct LocalClass {
+          int Method() { return 0; }
+        };
+      return 0;
+    }(0);
+    return d; }()
+  );
+};
+
+class Enclosing2 {
+  void Method(char c = [](auto x)->char {
+    int d = []()->int {
+        struct LocalClass {
+          int Method() { return 0; }
+        };
+      return 0;
+    }();
+    return d; }(0)
+  );
+};
+
+class Enclosing3 {
+  void Method(char c = [](auto x)->char {
+    int d = [](auto y)->int {
+        struct LocalClass {
+          int Method() { return 0; }
+        };
+      return 0;
+    }(0);
+    return d; }(0)
+  );
+};
+}

clang/test/SemaCXX/lambda-expressions.cpp

@@ -446,3 +446,33 @@ namespace PR21857 {
   template<typename Fn> fun<Fn> wrap(Fn fn);
   auto x = wrap([](){});
 }
+
+namespace PR13987 {
+class Enclosing {
+  void Method(char c = []()->char {
+    int d = []()->int {
+        struct LocalClass {
+          int Method() { return 0; }
+        };
+      return 0;
+    }();
+    return d; }()
+  );
+};
+}
+
+namespace PR23860 {
+template <class> struct A {
+  void f(int x = []() {
+    struct B {
+      void g() {}
+    };
+    return 0;
+  }());
+};
+
+int main() {
+}
+
+A<int> a;
+}