Merging r321754:

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r321754 | adrian | 2018-01-03 11:10:21 -0800 (Wed, 03 Jan 2018) | 9 lines

-gmodules: Emit debug info for implicit module imports via #include.

When a type is only used as a template parameter and that type is the
only type imported from another #include'd module, no skeleton CU for
that module is generated, so a consumer doesn't know where to find the
type definition. By emitting an import declaration, we can force a
skeleton CU to be generated for each imported module.

rdar://problem/36266156
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_60@322557 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/CodeGen/ObjectFilePCHContainerOperations.cpp b/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
index d0760b9cc2..0fe9f5da07 100644
--- a/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
+++ b/lib/CodeGen/ObjectFilePCHContainerOperations.cpp
@@ -229,6 +229,11 @@ public:
       Builder->getModuleDebugInfo()->completeRequiredType(RD);
   }
 
+  void HandleImplicitImportDecl(ImportDecl *D) override {
+    if (!D->getImportedOwningModule())
+      Builder->getModuleDebugInfo()->EmitImportDecl(*D);
+  }
+
   /// Emit a container holding the serialized AST.
   void HandleTranslationUnit(ASTContext &Ctx) override {
     assert(M && VMContext && Builder);