[modules] When parsing the base specifiers of a parse-merged class, the current

context is the class itself but lookups should be performed starting with the
lookup parent of the class (class and base members don't shadow types from the
surrounding context because they have not been declared yet).

llvm-svn: 245236

clang/lib/Sema/SemaDecl.cpp

@@ -1089,7 +1089,9 @@ Sema::SkippedDefinitionContext Sema::ActOnTagStartSkippedDefinition(Scope *S,
   auto Result = static_cast<SkippedDefinitionContext>(CurContext);
   CurContext = cast<TagDecl>(D)->getDefinition();
   assert(CurContext && "skipping definition of undefined tag");
-  S->setEntity(CurContext);
+  // Start lookups from the parent of the current context; we don't want to look
+  // into the pre-existing complete definition.
+  S->setEntity(CurContext->getLookupParent());
   return Result;
 }
 

clang/test/Modules/Inputs/submodules-merge-defs/defs.h

@@ -5,10 +5,17 @@ class B {
   struct Inner1 {};
 public:
   struct Inner2;
+  struct Inner3;
   template<typename T> void f();
 };
+struct BFriend {
+  friend class B::Inner3;
+private:
+  struct Inner3Base {};
+};
 // Check that lookup and access checks are performed in the right context.
 struct B::Inner2 : Inner1 {};
+struct B::Inner3 : BFriend::Inner3Base {};
 template<typename T> void B::f() {}
 template<> inline void B::f<int>() {}
 

clang/test/Modules/Inputs/template-default-args/a.h

@@ -6,4 +6,7 @@ template<typename T> struct D;
 template<typename T> struct E;
 template<typename T = int> struct G;
 template<typename T = int> struct H;
+template<typename T> struct J {};
+template<typename T = int> struct J;
+struct K : J<> {};
 END

clang/test/Modules/submodules-merge-defs.cpp

@@ -26,38 +26,38 @@ int pre_use_a = use_a(pre_a); // expected-error {{'A' must be imported}} expecte
 
 B::Inner2 pre_bi; // expected-error +{{must be imported}}
 // expected-note@defs.h:4 +{{here}}
-// expected-note@defs.h:11 +{{here}}
+// expected-note@defs.h:17 +{{here}}
 void pre_bfi(B b) { // expected-error {{must use 'class'}} expected-error +{{must be imported}}
   b.f<int>(); // expected-error +{{must be imported}} expected-error +{{}}
-  // expected-note@defs.h:12 +{{here}}
+  // expected-note@defs.h:19 +{{here}}
 }
 
 C_Base<1> pre_cb1; // expected-error +{{must be imported}}
-// expected-note@defs.h:16 +{{here}}
+// expected-note@defs.h:23 +{{here}}
 C1 pre_c1; // expected-error +{{must be imported}} expected-error {{must use 'struct'}}
-// expected-note@defs.h:18 +{{here}}
+// expected-note@defs.h:25 +{{here}}
 C2 pre_c2; // expected-error +{{must be imported}} expected-error {{must use 'struct'}}
-// expected-note@defs.h:19 +{{here}}
+// expected-note@defs.h:26 +{{here}}
 
 D::X pre_dx; // expected-error +{{must be imported}}
-// expected-note@defs.h:21 +{{here}}
-// expected-note@defs.h:22 +{{here}}
+// expected-note@defs.h:28 +{{here}}
+// expected-note@defs.h:29 +{{here}}
 // FIXME: We should warn that use_dx is being used without being imported.
 int pre_use_dx = use_dx(pre_dx);
 
 int pre_e = E(0); // expected-error {{must be imported}}
-// expected-note@defs.h:25 +{{here}}
+// expected-note@defs.h:32 +{{here}}
 
 int pre_ff = F<int>().f(); // expected-error +{{must be imported}}
 int pre_fg = F<int>().g<int>(); // expected-error +{{must be imported}}
-// expected-note@defs.h:27 +{{here}}
+// expected-note@defs.h:34 +{{here}}
 
 G::A pre_ga // expected-error +{{must be imported}}
   = G::a; // expected-error +{{must be imported}}
-// expected-note@defs.h:42 +{{here}}
-// expected-note@defs.h:43 +{{here}}
+// expected-note@defs.h:49 +{{here}}
+// expected-note@defs.h:50 +{{here}}
 decltype(G::h) pre_gh = G::h; // expected-error +{{must be imported}}
-// expected-note@defs.h:44 +{{here}}
+// expected-note@defs.h:51 +{{here}}
 
 J<> pre_j; // expected-error {{declaration of 'J' must be imported}}
 #ifdef IMPORT_USE_2
@@ -67,10 +67,10 @@ J<> pre_j; // expected-error {{declaration of 'J' must be imported}}
 #else
 // expected-error@-6 {{default argument of 'J' must be imported from module 'stuff.use'}}
 #endif
-// expected-note@defs.h:51 +{{here}}
+// expected-note@defs.h:58 +{{here}}
 
 ScopedEnum pre_scopedenum; // expected-error {{must be imported}} expected-error {{must use 'enum'}}
-// expected-note@defs.h:99 {{here}}
+// expected-note@defs.h:106 {{here}}
 enum ScopedEnum : int;
 ScopedEnum pre_scopedenum_declared; // ok
 

clang/test/Modules/template-default-args.cpp

@@ -22,6 +22,9 @@ template<typename T = int> struct C;
 template<typename T> struct D {};
 template<typename T> struct F {};
 template<typename T> struct G {};
+template<typename T> struct J {};
+template<typename T = int> struct J;
+struct K : J<> {};
 END
 
 #include "c.h"