8 files changed, 61 insertions, 22 deletions
diff --git a/clang/include/clang/Serialization/ASTReader.h b/clang/include/clang/Serialization/ASTReader.h
index 12d27f105f2..1b3d46a6e47 100644
--- a/clang/include/clang/Serialization/ASTReader.h
+++ b/clang/include/clang/Serialization/ASTReader.h
@@ -2076,9 +2076,9 @@ public:
   /// \brief Retrieve the AST context that this AST reader supplements.
   ASTContext &getContext() { return Context; }
 
-  // \brief Contains declarations that were loaded before we have
+  // \brief Contains the IDs for declarations that were requested before we have
   // access to a Sema object.
-  SmallVector<NamedDecl *, 16> PreloadedDecls;
+  SmallVector<uint64_t, 16> PreloadedDeclIDs;
 
   /// \brief Retrieve the semantic analysis object used to analyze the
   /// translation unit in which the precompiled header is being
diff --git a/clang/lib/Frontend/PrintPreprocessedOutput.cpp b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
index 17d7279e3ff..7c1d9a56883 100644
--- a/clang/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/clang/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -332,7 +332,10 @@ void PrintPPOutputPPCallbacks::InclusionDirective(SourceLocation HashLoc,
     MoveToLine(HashLoc);
     OS << "@import " << Imported->getFullModuleName() << ";"
        << " /* clang -E: implicit import for \"" << File->getName() << "\" */";
+    // Since we want a newline after the @import, but not a #<line>, start a new
+    // line immediately.
     EmittedTokensOnThisLine = true;
+    startNewLineIfNeeded();
   }
 }
 
diff --git a/clang/lib/Lex/TokenConcatenation.cpp b/clang/lib/Lex/TokenConcatenation.cpp
index 0a66bba91fc..866cbb142c8 100644
--- a/clang/lib/Lex/TokenConcatenation.cpp
+++ b/clang/lib/Lex/TokenConcatenation.cpp
@@ -163,8 +163,8 @@ bool TokenConcatenation::AvoidConcat(const Token &PrevPrevTok,
     return false;
 
   tok::TokenKind PrevKind = PrevTok.getKind();
-  if (PrevTok.getIdentifierInfo())  // Language keyword or named operator.
-    PrevKind = tok::identifier;
+  if (!PrevTok.isAnnotation() && PrevTok.getIdentifierInfo())
+    PrevKind = tok::identifier; // Language keyword or named operator.
 
   // Look up information on when we should avoid concatenation with prevtok.
   unsigned ConcatInfo = TokenInfo[PrevKind];
@@ -178,6 +178,14 @@ bool TokenConcatenation::AvoidConcat(const Token &PrevPrevTok,
       return true;
     ConcatInfo &= ~aci_avoid_equal;
   }
+  if (Tok.isAnnotation()) {
+    // Modules annotation can show up when generated automatically for includes.
+    assert((Tok.is(tok::annot_module_include) ||
+            Tok.is(tok::annot_module_begin) ||
+            Tok.is(tok::annot_module_end)) &&
+           "unexpected annotation in AvoidConcat");
+    ConcatInfo = 0;
+  }
 
   if (ConcatInfo == 0) return false;
 
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 8f1d88c6d58..93c01cb1e12 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -6893,11 +6893,11 @@ void ASTReader::InitializeSema(Sema &S) {
 
   // Makes sure any declarations that were deserialized "too early"
   // still get added to the identifier's declaration chains.
-  for (unsigned I = 0, N = PreloadedDecls.size(); I != N; ++I) {
-    pushExternalDeclIntoScope(PreloadedDecls[I],
-                              PreloadedDecls[I]->getDeclName());
+  for (uint64_t ID : PreloadedDeclIDs) {
+    NamedDecl *D = cast<NamedDecl>(GetDecl(ID));
+    pushExternalDeclIntoScope(D, D->getDeclName());
   }
-  PreloadedDecls.clear();
+  PreloadedDeclIDs.clear();
 
   // FIXME: What happens if these are changed by a module import?
   if (!FPPragmaOptions.empty()) {
@@ -7349,24 +7349,26 @@ ASTReader::SetGloballyVisibleDecls(IdentifierInfo *II,
   }
 
   for (unsigned I = 0, N = DeclIDs.size(); I != N; ++I) {
-    NamedDecl *D = cast<NamedDecl>(GetDecl(DeclIDs[I]));
-    if (SemaObj) {
-      // If we're simply supposed to record the declarations, do so now.
-      if (Decls) {
-        Decls->push_back(D);
-        continue;
-      }
-
-      // Introduce this declaration into the translation-unit scope
-      // and add it to the declaration chain for this identifier, so
-      // that (unqualified) name lookup will find it.
-      pushExternalDeclIntoScope(D, II);
-    } else {
+    if (!SemaObj) {
       // Queue this declaration so that it will be added to the
       // translation unit scope and identifier's declaration chain
       // once a Sema object is known.
-      PreloadedDecls.push_back(D);
+      PreloadedDeclIDs.push_back(DeclIDs[I]);
+      continue;
     }
+
+    NamedDecl *D = cast<NamedDecl>(GetDecl(DeclIDs[I]));
+
+    // If we're simply supposed to record the declarations, do so now.
+    if (Decls) {
+      Decls->push_back(D);
+      continue;
+    }
+
+    // Introduce this declaration into the translation-unit scope
+    // and add it to the declaration chain for this identifier, so
+    // that (unqualified) name lookup will find it.
+    pushExternalDeclIntoScope(D, II);
   }
 }
 
diff --git a/clang/test/Modules/Inputs/diamond_left.h b/clang/test/Modules/Inputs/diamond_left.h
index fce2e48882f..6494551e4bf 100644
--- a/clang/test/Modules/Inputs/diamond_left.h
+++ b/clang/test/Modules/Inputs/diamond_left.h
@@ -1,3 +1,5 @@
+int top_left_before(void *);
+
 @import diamond_top;
 
 float left(float *);
diff --git a/clang/test/Modules/Inputs/diamond_top.h b/clang/test/Modules/Inputs/diamond_top.h
index 34998cd4324..30da14f6449 100644
--- a/clang/test/Modules/Inputs/diamond_top.h
+++ b/clang/test/Modules/Inputs/diamond_top.h
@@ -2,3 +2,4 @@ int top(int *);
 
 int top_left(char *c);
 
+int top_left_before(void *);
diff --git a/clang/test/Modules/Inputs/preprocess-prefix.h b/clang/test/Modules/Inputs/preprocess-prefix.h
new file mode 100644
index 00000000000..04d01758320
--- /dev/null
+++ b/clang/test/Modules/Inputs/preprocess-prefix.h
@@ -0,0 +1,2 @@
+int left_and_right(int *);
+#import "diamond_left.h"
diff --git a/clang/test/Modules/preprocess.m b/clang/test/Modules/preprocess.m
new file mode 100644
index 00000000000..a1c024d6ffb
--- /dev/null
+++ b/clang/test/Modules/preprocess.m
@@ -0,0 +1,21 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %S/Inputs -include %S/Inputs/preprocess-prefix.h -E %s | FileCheck -strict-whitespace %s
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %S/Inputs -x objective-c-header -emit-pch %S/Inputs/preprocess-prefix.h -o %t.pch
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %S/Inputs -include-pch %t.pch -E %s | FileCheck -strict-whitespace %s
+#import "diamond_right.h"
+#import "diamond_right.h" // to check that imports get their own line
+void test() {
+  top_left_before();
+  left_and_right();
+}
+
+
+// CHECK: int left_and_right(int *);{{$}}
+// CHECK-NEXT: @import diamond_left; /* clang -E: implicit import for "{{.*}}diamond_left.h" */{{$}}
+
+// CHECK: @import diamond_right; /* clang -E: implicit import for "/Users/blangmuir/src/clang/test/Modules/Inputs/diamond_right.h" */{{$}}
+// CHECK: @import diamond_right; /* clang -E: implicit import for "/Users/blangmuir/src/clang/test/Modules/Inputs/diamond_right.h" */{{$}}
+// CHECK-NEXT: void test() {{{$}}
+// CHECK-NEXT:    top_left_before();{{$}}
+// CHECK-NEXT:    left_and_right();{{$}}
+// CHECK-NEXT: }{{$}}