[modules] Fix merging support for forward-declared enums with fixed underlying types. A visible declaration is enough to make the type complete, but not enough to make the definition visible.

llvm-svn: 241743

2 files changed, 8 insertions, 0 deletions

diff --git a/clang/test/Modules/Inputs/submodules-merge-defs/defs.h b/clang/test/Modules/Inputs/submodules-merge-defs/defs.h
index bda0567c93a..07dfac7ee65 100644
--- a/clang/test/Modules/Inputs/submodules-merge-defs/defs.h
+++ b/clang/test/Modules/Inputs/submodules-merge-defs/defs.h
@@ -94,3 +94,6 @@ namespace MergeFunctionTemplateSpecializations {
   };
   using xiq = X<int>::Q<int>;
 }
+
+enum ScopedEnum : int;
+enum ScopedEnum : int { a, b, c };
diff --git a/clang/test/Modules/submodules-merge-defs.cpp b/clang/test/Modules/submodules-merge-defs.cpp
index 92c784440b9..016b8a8f47a 100644
--- a/clang/test/Modules/submodules-merge-defs.cpp
+++ b/clang/test/Modules/submodules-merge-defs.cpp
@@ -69,6 +69,11 @@ J<> pre_j; // expected-error {{declaration of 'J' must be imported}}
 #endif
 // expected-note@defs.h:51 +{{here}}
 
+ScopedEnum pre_scopedenum; // expected-error {{must be imported}} expected-error {{must use 'enum'}}
+// expected-note@defs.h:99 {{here}}
+enum ScopedEnum : int;
+ScopedEnum pre_scopedenum_declared; // ok
+
 // Make definitions from second module visible.
 #ifdef TEXTUAL
 #include "import-and-redefine.h"