[PCH] After deserializing a DeclContext, if it has external lexical decls but not

external visible decls, call DeclContext::setMustBuildLookupTable so that the
"lazy decls" bit of the LookupPtr is set.

Previously, in non-C++, if there were no new declarations causing the "lazy decls" bit
to be set, then DeclContext::lookups_begin() would fail to return the decls from the PCH.

Fixes rdar://12316296.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@164351 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 7 insertions, 0 deletions

diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index 478217bd03..9fe6ef317e 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -1661,6 +1661,10 @@ ASTReader::ReadASTBlock(ModuleFile &F) {
         return Failure;
       }
 
+      DeclContext *DC = Context.getTranslationUnitDecl();
+      if (!DC->hasExternalVisibleStorage() && DC->hasExternalLexicalStorage())
+        DC->setMustBuildLookupTable();
+
       return Success;
     }
 
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 754ff36db7..c9788a3216 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -2127,6 +2127,9 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
       }
       PendingVisibleUpdates.erase(I);
     }
+
+    if (!DC->hasExternalVisibleStorage() && DC->hasExternalLexicalStorage())
+      DC->setMustBuildLookupTable();
   }
   assert(Idx == Record.size());