Emit a nicer diagnostic for misplaced attributes on ObjC directives.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178670 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 43 insertions, 8 deletions

diff --git a/include/clang/Basic/DiagnosticParseKinds.td b/include/clang/Basic/DiagnosticParseKinds.td
index d0bddae1e0..26820dbddf 100644
--- a/include/clang/Basic/DiagnosticParseKinds.td
+++ b/include/clang/Basic/DiagnosticParseKinds.td
@@ -399,6 +399,8 @@ def err_objc_properties_require_objc2 : Error<
   "properties are an Objective-C 2 feature">;
 def err_objc_unexpected_attr : Error<
   "prefix attribute must be followed by an interface or protocol">;
+def err_objc_postfix_attribute : Error <
+  "postfix attributes are not allowed on Objective-C directives">;
 def err_objc_directive_only_in_protocol : Error<
   "directive may only be specified in protocols only">;
 def err_missing_catch_finally : Error<
diff --git a/include/clang/Parse/Parser.h b/include/clang/Parse/Parser.h
index 11a3bdbd50..7ff6f96ff9 100644
--- a/include/clang/Parse/Parser.h
+++ b/include/clang/Parse/Parser.h
@@ -1113,6 +1113,7 @@ private:
   ExprResult ParseAsmStringLiteral();
 
   // Objective-C External Declarations
+  void MaybeSkipAttributes();
   DeclGroupPtrTy ParseObjCAtDirectives();
   DeclGroupPtrTy ParseObjCAtClassDeclaration(SourceLocation atLoc);
   Decl *ParseObjCAtInterfaceDeclaration(SourceLocation AtLoc,
diff --git a/lib/Parse/ParseObjc.cpp b/lib/Parse/ParseObjc.cpp
index fb0237ac05..844a3d12e9 100644
--- a/lib/Parse/ParseObjc.cpp
+++ b/lib/Parse/ParseObjc.cpp
@@ -22,6 +22,14 @@
 #include "llvm/ADT/StringExtras.h"
 using namespace clang;
 
+/// Skips attributes after an Objective-C @ directive. Emits a diagnostic.
+void Parser::MaybeSkipAttributes() {
+  ParsedAttributes attrs(AttrFactory);
+  if (Tok.is(tok::kw___attribute)) {
+    Diag(Tok, diag::err_objc_postfix_attribute);
+    ParseGNUAttributes(attrs);
+  }
+}
 
 /// ParseObjCAtDirectives - Handle parts of the external-declaration production:
 ///       external-declaration: [C99 6.9]
@@ -93,6 +101,7 @@ Parser::ParseObjCAtClassDeclaration(SourceLocation atLoc) {
 
 
   while (1) {
+    MaybeSkipAttributes();
     if (Tok.isNot(tok::identifier)) {
       Diag(Tok, diag::err_expected_ident);
       SkipUntil(tok::semi);
@@ -179,6 +188,8 @@ Decl *Parser::ParseObjCAtInterfaceDeclaration(SourceLocation AtLoc,
     return 0;
   }
 
+  MaybeSkipAttributes();
+
   if (Tok.isNot(tok::identifier)) {
     Diag(Tok, diag::err_expected_ident); // missing class or category name.
     return 0;
@@ -1397,6 +1408,8 @@ Parser::ParseObjCAtProtocolDeclaration(SourceLocation AtLoc,
     return DeclGroupPtrTy();
   }
 
+  MaybeSkipAttributes();
+
   if (Tok.isNot(tok::identifier)) {
     Diag(Tok, diag::err_expected_ident); // missing protocol name.
     return DeclGroupPtrTy();
@@ -1488,6 +1501,8 @@ Parser::ParseObjCAtImplementationDeclaration(SourceLocation AtLoc) {
     return DeclGroupPtrTy();
   }
 
+  MaybeSkipAttributes();
+
   if (Tok.isNot(tok::identifier)) {
     Diag(Tok, diag::err_expected_ident); // missing class or category name.
     return DeclGroupPtrTy();
diff --git a/test/Parser/attributes.mm b/test/Parser/attributes.mm
new file mode 100644
index 0000000000..812d543e3e
--- /dev/null
+++ b/test/Parser/attributes.mm
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -verify -fsyntax-only -Wno-objc-root-class %s
+
+__attribute__((deprecated)) @class B; // expected-error {{prefix attribute must be followed by an interface or protocol}}
+
+__attribute__((deprecated)) @interface A @end
+__attribute__((deprecated)) @protocol P0;
+__attribute__((deprecated)) @protocol P1
+@end
+
+#define EXP __attribute__((visibility("default")))
+class EXP C {};
+EXP class C2 {}; // expected-warning {{attribute 'visibility' is ignored, place it after "class" to apply attribute to type declaration}}
+
+@interface EXP I @end // expected-error {{postfix attributes are not allowed on Objective-C directives}}
+EXP @interface I2 @end
+
+@implementation EXP I @end // expected-error {{postfix attributes are not allowed on Objective-C directives}}
+// FIXME: Prefix attribute recovery skips until ';'
+EXP @implementation I2 @end; // expected-error{{prefix attribute must be followed by an interface or protocol}}
+
+@class EXP OC; // expected-error {{postfix attributes are not allowed on Objective-C directives}}
+EXP @class OC2; // expected-error {{prefix attribute must be followed by an interface or protocol}}
+
+@protocol EXP P @end // expected-error {{postfix attributes are not allowed on Objective-C directives}}
+EXP @protocol P2 @end
diff --git a/test/Parser/prefix-attributes.m b/test/Parser/prefix-attributes.m
deleted file mode 100644
index 399421fd72..0000000000
--- a/test/Parser/prefix-attributes.m
+++ /dev/null
@@ -1,8 +0,0 @@
-// RUN: %clang_cc1 -verify -fsyntax-only %s
-
-__attribute__((deprecated)) @class B; // expected-error {{prefix attribute must be followed by an interface or protocol}}
-
-__attribute__((deprecated)) @interface A @end
-__attribute__((deprecated)) @protocol P0;
-__attribute__((deprecated)) @protocol P1
-@end