20 files changed, 115 insertions, 22 deletions

diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
index 3f866813038..291eca2d717 100644
--- a/clang/include/clang/Basic/DiagnosticParseKinds.td
+++ b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1013,6 +1013,7 @@ def err_module_expected_ident : Error<
   "expected a module name after module import">;
 def err_module_expected_semi : Error<
   "expected ';' after module name">;
+def err_missing_before_module_end : Error<"expected %0 at end of module">;
 }
 
 let CategoryName = "Generics Issue" in {
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 7d22327961b..3432b6c2687 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -7776,6 +7776,8 @@ def note_module_import_in_extern_c : Note<
   "extern \"C\" language linkage specification begins here">;
 def err_module_import_not_at_top_level : Error<
   "import of module '%0' appears within %1">;
+def err_module_import_not_at_top_level_fatal : Error<
+  "import of module '%0' appears within %1">, DefaultFatal;
 def note_module_import_not_at_top_level : Note<"%0 begins here">;
 def err_module_self_import : Error<
   "import of module '%0' appears within same top-level module '%1'">;
diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h
index 272b504d1e0..54bac154894 100644
--- a/clang/include/clang/Parse/Parser.h
+++ b/clang/include/clang/Parse/Parser.h
@@ -2555,6 +2555,14 @@ private:
   //===--------------------------------------------------------------------===//
   // Modules
   DeclGroupPtrTy ParseModuleImport(SourceLocation AtLoc);
+  bool parseMisplacedModuleImport();
+  bool tryParseMisplacedModuleImport() {
+    tok::TokenKind Kind = Tok.getKind();
+    if (Kind == tok::annot_module_begin || Kind == tok::annot_module_end ||
+        Kind == tok::annot_module_include)
+      return parseMisplacedModuleImport();
+    return false;
+  }
 
   //===--------------------------------------------------------------------===//
   // C++11/G++: Type Traits [Type-Traits.html in the GCC manual]
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index a7b74172a7e..b55db2e8cb6 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -1799,6 +1799,10 @@ public:
   /// \brief The parser has left a submodule.
   void ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod);
 
+  /// \brief Check if module import may be found in the current context,
+  /// emit error if not.
+  void diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc);
+
   /// \brief Create an implicit import of the given module at the given
   /// source location, for error recovery, if possible.
   ///
diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 80d25426f66..f5983c0295e 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -3589,7 +3589,8 @@ void Parser::ParseStructUnionBody(SourceLocation RecordLoc,
   SmallVector<Decl *, 32> FieldDecls;
 
   // While we still have something to read, read the declarations in the struct.
-  while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
+  while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof) &&
+         !tryParseMisplacedModuleImport()) {
     // Each iteration of this loop reads one struct-declaration.
 
     // Check for extraneous top-level semicolon.
diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp
index 1a0d262279f..5e59d5dba28 100644
--- a/clang/lib/Parse/ParseDeclCXX.cpp
+++ b/clang/lib/Parse/ParseDeclCXX.cpp
@@ -210,7 +210,8 @@ void Parser::ParseInnerNamespace(std::vector<SourceLocation> &IdentLoc,
                                  ParsedAttributes &attrs,
                                  BalancedDelimiterTracker &Tracker) {
   if (index == Ident.size()) {
-    while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
+    while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof) &&
+           !tryParseMisplacedModuleImport()) {
       ParsedAttributesWithRange attrs(AttrFactory);
       MaybeParseCXX11Attributes(attrs);
       MaybeParseMicrosoftAttributes(attrs);
@@ -3063,11 +3064,12 @@ void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
 
   if (TagDecl) {
     // While we still have something to read, read the member-declarations.
-    while (Tok.isNot(tok::r_brace) && !isEofOrEom())
+    while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof) &&
+           !tryParseMisplacedModuleImport()) {
       // Each iteration of this loop reads one member-declaration.
       ParseCXXClassMemberDeclarationWithPragmas(
           CurAS, AccessAttrs, static_cast<DeclSpec::TST>(TagType), TagDecl);
-
+    }
     T.consumeClose();
   } else {
     SkipUntil(tok::r_brace);
diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp
index b658cef234e..312c5e6f511 100644
--- a/clang/lib/Parse/ParseStmt.cpp
+++ b/clang/lib/Parse/ParseStmt.cpp
@@ -944,7 +944,8 @@ StmtResult Parser::ParseCompoundStatementBody(bool isStmtExpr) {
       Stmts.push_back(R.get());
   }
 
-  while (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
+  while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof) &&
+         !tryParseMisplacedModuleImport()) {
     if (Tok.is(tok::annot_pragma_unused)) {
       HandlePragmaUnused();
       continue;
diff --git a/clang/lib/Parse/Parser.cpp b/clang/lib/Parse/Parser.cpp
index 35e853f64fc..5b0704658a2 100644
--- a/clang/lib/Parse/Parser.cpp
+++ b/clang/lib/Parse/Parser.cpp
@@ -2018,6 +2018,37 @@ Parser::DeclGroupPtrTy Parser::ParseModuleImport(SourceLocation AtLoc) {
   return Actions.ConvertDeclToDeclGroup(Import.get());
 }
 
+/// \brief Try recover parser when module annotation appears where it must not
+/// be found.
+/// \returns false if the recover was successful and parsing may be continued, or
+/// true if parser must bail out to top level and handle the token there.
+bool Parser::parseMisplacedModuleImport() {
+  while (true) {
+    switch (Tok.getKind()) {
+    case tok::annot_module_end:
+      // Inform caller that recovery failed, the error must be handled at upper
+      // level.
+      return true;
+    case tok::annot_module_begin:
+      Actions.diagnoseMisplacedModuleImport(reinterpret_cast<Module *>(
+        Tok.getAnnotationValue()), Tok.getLocation());
+      return true;
+    case tok::annot_module_include:
+      // Module import found where it should not be, for instance, inside a
+      // namespace. Recover by importing the module.
+      Actions.ActOnModuleInclude(Tok.getLocation(),
+                                 reinterpret_cast<Module *>(
+                                 Tok.getAnnotationValue()));
+      ConsumeToken();
+      // If there is another module import, process it.
+      continue;
+    default:
+      return false;
+    }
+  }
+  return false;
+}
+
 bool BalancedDelimiterTracker::diagnoseOverflow() {
   P.Diag(P.Tok, diag::err_bracket_depth_exceeded)
     << P.getLangOpts().BracketDepth;
@@ -2045,7 +2076,10 @@ bool BalancedDelimiterTracker::expectAndConsume(unsigned DiagID,
 bool BalancedDelimiterTracker::diagnoseMissingClose() {
   assert(!P.Tok.is(Close) && "Should have consumed closing delimiter");
 
-  P.Diag(P.Tok, diag::err_expected) << Close;
+  if (P.Tok.is(tok::annot_module_end))
+    P.Diag(P.Tok, diag::err_missing_before_module_end) << Close;
+  else
+    P.Diag(P.Tok, diag::err_expected) << Close;
   P.Diag(LOpen, diag::note_matching) << Kind;
 
   // If we're not already at some kind of closing bracket, skip to our closing
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 701d8c72902..3101fda933c 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -14368,14 +14368,17 @@ static void checkModuleImportContext(Sema &S, Module *M,
   while (isa<LinkageSpecDecl>(DC))
     DC = DC->getParent();
   if (!isa<TranslationUnitDecl>(DC)) {
-    S.Diag(ImportLoc, diag::err_module_import_not_at_top_level)
-      << M->getFullModuleName() << DC;
+    S.Diag(ImportLoc, diag::err_module_import_not_at_top_level_fatal)
+        << M->getFullModuleName() << DC;
     S.Diag(cast<Decl>(DC)->getLocStart(),
-           diag::note_module_import_not_at_top_level)
-      << DC;
+           diag::note_module_import_not_at_top_level) << DC;
   }
 }
 
+void Sema::diagnoseMisplacedModuleImport(Module *M, SourceLocation ImportLoc) {
+  return checkModuleImportContext(*this, M, ImportLoc, CurContext);
+}
+
 DeclResult Sema::ActOnModuleImport(SourceLocation AtLoc, 
                                    SourceLocation ImportLoc, 
                                    ModuleIdPath Path) {
diff --git a/clang/test/Modules/Inputs/misplaced/misplaced-a.h b/clang/test/Modules/Inputs/misplaced/misplaced-a.h
new file mode 100644
index 00000000000..f50e5cefc3a
--- /dev/null
+++ b/clang/test/Modules/Inputs/misplaced/misplaced-a.h
@@ -0,0 +1,5 @@
+namespace A {
+  namespace B {  // expected-note{{namespace 'A::B' begins here}}
+    #include "misplaced-b.h"  // expected-error{{import of module 'Misplaced.Sub_B' appears within namespace 'A::B'}}
+  }
+}
diff --git a/clang/test/Modules/Inputs/misplaced/misplaced-b.h b/clang/test/Modules/Inputs/misplaced/misplaced-b.h
new file mode 100644
index 00000000000..68dd955ef82
--- /dev/null
+++ b/clang/test/Modules/Inputs/misplaced/misplaced-b.h
@@ -0,0 +1 @@
+int a;
\ No newline at end of file
diff --git a/clang/test/Modules/Inputs/misplaced/misplaced.modulemap b/clang/test/Modules/Inputs/misplaced/misplaced.modulemap
new file mode 100644
index 00000000000..50aa7a47e50
--- /dev/null
+++ b/clang/test/Modules/Inputs/misplaced/misplaced.modulemap
@@ -0,0 +1,8 @@
+module Misplaced {
+  module Sub_A {
+    header "misplaced-a.h"
+  }
+  module Sub_B {
+    header "misplaced-b.h"
+  }
+}
diff --git a/clang/test/Modules/auto-module-import.m b/clang/test/Modules/auto-module-import.m
index de2c355a424..76441fcfedc 100644
--- a/clang/test/Modules/auto-module-import.m
+++ b/clang/test/Modules/auto-module-import.m
@@ -83,6 +83,7 @@ int getNotInModule() {
   return not_in_module;
 }
 
-void includeNotAtTopLevel() { // expected-note {{to match this '{'}}
-  #include <NoUmbrella/A.h> // expected-warning {{treating #include as an import}} expected-error {{expected '}'}}
-} // expected-error {{extraneous closing brace}}
+void includeNotAtTopLevel() { // expected-note {{function 'includeNotAtTopLevel' begins here}}
+  #include <NoUmbrella/A.h> // expected-warning {{treating #include as an import}} \
+			       expected-error {{import of module 'NoUmbrella.A' appears within function 'includeNotAtTopLevel'}}
+}
diff --git a/clang/test/Modules/extern_c.cpp b/clang/test/Modules/extern_c.cpp
index f505c11f7c9..c9b4b8435fd 100644
--- a/clang/test/Modules/extern_c.cpp
+++ b/clang/test/Modules/extern_c.cpp
@@ -68,7 +68,7 @@ namespace N {
   extern "C" {
 #endif
     int f;
-#if !defined(CXX_HEADER)
+#if !defined(CXX_HEADER) && !defined(NAMESPACE)
     // expected-error@-2 {{redefinition of 'f' as different kind of symbol}}
     // expected-note@c-header.h:1 {{previous}}
 #endif
@@ -78,4 +78,6 @@ namespace N {
 }
 #endif
 
+#if !defined(NAMESPACE)
 suppress_expected_no_diagnostics_error error_here; // expected-error {{}}
+#endif
diff --git a/clang/test/Modules/malformed.cpp b/clang/test/Modules/malformed.cpp
index 7d5bcc8c9d6..040361c9eeb 100644
--- a/clang/test/Modules/malformed.cpp
+++ b/clang/test/Modules/malformed.cpp
@@ -12,20 +12,14 @@
 #include STR(HEADER)
 
 // CHECK-A: While building module 'malformed_a'
-// CHECK-A: {{^}}Inputs/malformed/a1.h:1:{{.*}} error: expected '}'
+// CHECK-A: {{^}}Inputs/malformed/a1.h:1:{{.*}} error: expected '}' at end of module
 // CHECK-A: {{^}}Inputs/malformed/a1.h:1:{{.*}} note: to match this '{'
 //
 // CHECK-A: While building module 'malformed_a'
 // CHECK-A: {{^}}Inputs/malformed/a2.h:1:{{.*}} error: extraneous closing brace
 
 // CHECK-B: While building module 'malformed_b'
-// CHECK-B: {{^}}Inputs/malformed/b1.h:2:{{.*}} error: expected '}'
-// CHECK-B: {{^}}Inputs/malformed/b1.h:1:{{.*}} note: to match this '{'
-// CHECK-B: {{^}}Inputs/malformed/b1.h:3:{{.*}} error: extraneous closing brace ('}')
-//
-// CHECK-B: While building module 'malformed_b'
-// CHECK-B: {{^}}Inputs/malformed/b2.h:1:{{.*}} error: redefinition of 'g'
-// CHECK-B: {{^}}Inputs/malformed/b2.h:1:{{.*}} note: previous definition is here
+// CHECK-B: {{^}}Inputs/malformed/b1.h:2:{{.*}} error: import of module 'malformed_b.b2' appears within 'S'
 
 void test() { f<int>(); }
 // Test that we use relative paths to name files within an imported module.
diff --git a/clang/test/Modules/misplaced-1.cpp b/clang/test/Modules/misplaced-1.cpp
new file mode 100644
index 00000000000..d67ad194a92
--- /dev/null
+++ b/clang/test/Modules/misplaced-1.cpp
@@ -0,0 +1,6 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify
+
+namespace N1 {  // expected-note{{namespace 'N1' begins here}}
+#include "dummy.h"  // expected-error{{import of module 'dummy' appears within namespace 'N1'}}
+}
diff --git a/clang/test/Modules/misplaced-2.cpp b/clang/test/Modules/misplaced-2.cpp
new file mode 100644
index 00000000000..da460993868
--- /dev/null
+++ b/clang/test/Modules/misplaced-2.cpp
@@ -0,0 +1,6 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify
+
+void func1() {  // expected-note{{function 'func1' begins here}}
+#include "dummy.h"  // expected-error{{import of module 'dummy' appears within function 'func1'}}
+}
diff --git a/clang/test/Modules/misplaced-3.cpp b/clang/test/Modules/misplaced-3.cpp
new file mode 100644
index 00000000000..6d18e13ecbf
--- /dev/null
+++ b/clang/test/Modules/misplaced-3.cpp
@@ -0,0 +1,6 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify
+
+class C1 {  // expected-note{{'C1' begins here}}
+#include "dummy.h"  // expected-error{{import of module 'dummy' appears within 'C1'}}
+}
diff --git a/clang/test/Modules/misplaced-4.cpp b/clang/test/Modules/misplaced-4.cpp
new file mode 100644
index 00000000000..8f795d5c50f
--- /dev/null
+++ b/clang/test/Modules/misplaced-4.cpp
@@ -0,0 +1,2 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -emit-module -fmodule-name=Misplaced -fmodules-cache-path=%t -x c++ -I %S/Inputs %S/Inputs/misplaced/misplaced.modulemap -verify
diff --git a/clang/test/Modules/misplaced-5.c b/clang/test/Modules/misplaced-5.c
new file mode 100644
index 00000000000..ae4b3f5d8b4
--- /dev/null
+++ b/clang/test/Modules/misplaced-5.c
@@ -0,0 +1,6 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I %S/Inputs %s -verify
+
+struct S1 {  // expected-note{{'struct S1' begins here}}
+#include "dummy.h"  // expected-error{{import of module 'dummy' appears within 'struct S1'}}
+}