Take care another assert:

struct A {
  struct B;
};

struct A::B {
  void m() {} // Assertion failed: getContainingDC(DC) == CurContext && "The next DeclContext should be lexically contained in the current one."
};

Introduce DeclContext::getLexicalParent which may be different from DeclContext::getParent when nested-names are involved, e.g:

   namespace A {
      struct S;
   }
   struct A::S {}; // getParent() == namespace 'A'
                   // getLexicalParent() == translation unit


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59650 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index d6d9845..941f40f 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -53,10 +53,10 @@
     // A C++ inline method is parsed *after* the topmost class it was declared in
     // is fully parsed (it's "complete").
     // The parsing of a C++ inline method happens at the declaration context of
-    // the topmost (non-nested) class it is declared in.
+    // the topmost (non-nested) class it is lexically declared in.
     assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record.");
     DC = MD->getParent();
-    while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getParent()))
+    while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent()))
       DC = RD;
 
     // Return the declaration context of the topmost class the inline method is
@@ -70,7 +70,7 @@
   if (ScopedDecl *SD = dyn_cast<ScopedDecl>(DC))
     return SD->getLexicalDeclContext();
 
-  return DC->getParent();
+  return DC->getLexicalParent();
 }
 
 void Sema::PushDeclContext(DeclContext *DC) {