1 files changed, 25 insertions, 18 deletions

diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 1c08cbf53a7..ba42cd3173d 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -3103,6 +3103,7 @@ class ASTIdentifierTableTrait {
   Preprocessor &PP;
   IdentifierResolver &IdResolver;
   bool IsModule;
+  bool NeedDecls;
   
   /// \brief Determines whether this is an "interesting" identifier that needs a
   /// full IdentifierInfo structure written into the hash table. Notably, this
@@ -3113,7 +3114,7 @@ class ASTIdentifierTableTrait {
         II->isPoisoned() ||
         (IsModule ? II->hasRevertedBuiltin() : II->getObjCOrBuiltinID()) ||
         II->hasRevertedTokenIDToIdentifier() ||
-        II->getFETokenInfo<void>())
+        (NeedDecls && II->getFETokenInfo<void>()))
       return true;
 
     return false;
@@ -3131,7 +3132,8 @@ public:
 
   ASTIdentifierTableTrait(ASTWriter &Writer, Preprocessor &PP,
                           IdentifierResolver &IdResolver, bool IsModule)
-      : Writer(Writer), PP(PP), IdResolver(IdResolver), IsModule(IsModule) {}
+      : Writer(Writer), PP(PP), IdResolver(IdResolver), IsModule(IsModule),
+        NeedDecls(!IsModule || !Writer.getLangOpts().CPlusPlus) {}
 
   static hash_value_type ComputeHash(const IdentifierInfo* II) {
     return llvm::HashString(II->getName());
@@ -3152,10 +3154,12 @@ public:
       if (MacroOffset)
         DataLen += 4; // MacroDirectives offset.
 
-      for (IdentifierResolver::iterator D = IdResolver.begin(II),
-                                     DEnd = IdResolver.end();
-           D != DEnd; ++D)
-        DataLen += 4;
+      if (NeedDecls) {
+        for (IdentifierResolver::iterator D = IdResolver.begin(II),
+                                       DEnd = IdResolver.end();
+             D != DEnd; ++D)
+          DataLen += 4;
+      }
     }
     using namespace llvm::support;
     endian::Writer<little> LE(Out);
@@ -3205,18 +3209,21 @@ public:
     if (HadMacroDefinition)
       LE.write<uint32_t>(MacroOffset);
 
-    // Emit the declaration IDs in reverse order, because the
-    // IdentifierResolver provides the declarations as they would be
-    // visible (e.g., the function "stat" would come before the struct
-    // "stat"), but the ASTReader adds declarations to the end of the list
-    // (so we need to see the struct "stat" before the function "stat").
-    // Only emit declarations that aren't from a chained PCH, though.
-    SmallVector<NamedDecl *, 16> Decls(IdResolver.begin(II), IdResolver.end());
-    for (SmallVectorImpl<NamedDecl *>::reverse_iterator D = Decls.rbegin(),
-                                                        DEnd = Decls.rend();
-         D != DEnd; ++D)
-      LE.write<uint32_t>(
-          Writer.getDeclID(getDeclForLocalLookup(PP.getLangOpts(), *D)));
+    if (NeedDecls) {
+      // Emit the declaration IDs in reverse order, because the
+      // IdentifierResolver provides the declarations as they would be
+      // visible (e.g., the function "stat" would come before the struct
+      // "stat"), but the ASTReader adds declarations to the end of the list
+      // (so we need to see the struct "stat" before the function "stat").
+      // Only emit declarations that aren't from a chained PCH, though.
+      SmallVector<NamedDecl *, 16> Decls(IdResolver.begin(II),
+                                         IdResolver.end());
+      for (SmallVectorImpl<NamedDecl *>::reverse_iterator D = Decls.rbegin(),
+                                                          DEnd = Decls.rend();
+           D != DEnd; ++D)
+        LE.write<uint32_t>(
+            Writer.getDeclID(getDeclForLocalLookup(PP.getLangOpts(), *D)));
+    }
   }
 };
 } // end anonymous namespace