From 66a985d16ee1c65a43f27bb56f2e8859c8f5110c Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Wed, 26 Aug 2009 14:27:30 +0000
Subject: [PATCH] Fix bug in __extension__ handling for declarations, from
 Abramo Bagnara with a fix from Enea Zaffanella!

llvm-svn: 80094
---
 clang/include/clang/Basic/Diagnostic.h |  1 +
 clang/include/clang/Parse/DeclSpec.h   |  8 +++++++-
 clang/lib/Parse/ParseDecl.cpp          | 17 ++++++++++++++---
 clang/test/Sema/implicit-int.c         |  2 +-
 4 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/clang/include/clang/Basic/Diagnostic.h b/clang/include/clang/Basic/Diagnostic.h
index 8a09fa59ab19..226cbe893cb3 100644
--- a/clang/include/clang/Basic/Diagnostic.h
+++ b/clang/include/clang/Basic/Diagnostic.h
@@ -256,6 +256,7 @@ public:
   /// entirely silenced, no matter how they are mapped.
   void IncrementAllExtensionsSilenced() { ++AllExtensionsSilenced; }
   void DecrementAllExtensionsSilenced() { --AllExtensionsSilenced; }
+  bool hasAllExtensionsSilenced() { return AllExtensionsSilenced != 0; }
   
   /// setDiagnosticMapping - This allows the client to specify that certain
   /// warnings are ignored.  Notes can never be mapped, errors can only be
diff --git a/clang/include/clang/Parse/DeclSpec.h b/clang/include/clang/Parse/DeclSpec.h
index 06d05f7bc718..9d8a6f07988a 100644
--- a/clang/include/clang/Parse/DeclSpec.h
+++ b/clang/include/clang/Parse/DeclSpec.h
@@ -853,6 +853,9 @@ private:
   DeclaratorChunk::ParamInfo InlineParams[16];
   bool InlineParamsUsed;
 
+  /// Extension - true if the declaration is preceded by __extension__.
+  bool Extension : 1;
+
   friend struct DeclaratorChunk;
 
 public:
@@ -861,7 +864,7 @@ public:
       Kind(DK_Abstract),
       InvalidType(DS.getTypeSpecType() == DeclSpec::TST_error),
       GroupingParens(false), AttrList(0), AsmLabel(0), Type(0),
-      InlineParamsUsed(false) {
+      InlineParamsUsed(false), Extension(false) {
   }
   
   ~Declarator() {
@@ -1090,6 +1093,9 @@ public:
   void setAsmLabel(ActionBase::ExprTy *E) { AsmLabel = E; }
   ActionBase::ExprTy *getAsmLabel() const { return AsmLabel; }
 
+  void setExtension(bool Val = true) { Extension = Val; }
+  bool getExtension() const { return Extension; }
+
   ActionBase::TypeTy *getDeclaratorIdType() const { return Type; }
 
   OverloadedOperatorKind getOverloadedOperator() const { return OperatorKind; }
diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 8cb8ffdd0542..c29f601f2996 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -1509,10 +1509,19 @@ void Parser::ParseStructUnionBody(SourceLocation RecordLoc,
       // Convert them all to fields.
       for (unsigned i = 0, e = FieldDeclarators.size(); i != e; ++i) {
         FieldDeclarator &FD = FieldDeclarators[i];
+        DeclPtrTy Field;
         // Install the declarator into the current TagDecl.
-        DeclPtrTy Field = Actions.ActOnField(CurScope, TagDecl,
-                                             DS.getSourceRange().getBegin(),
-                                             FD.D, FD.BitfieldSize);
+        if (FD.D.getExtension()) {
+          // Silences extension warnings
+          ExtensionRAIIObject O(Diags);
+          Field = Actions.ActOnField(CurScope, TagDecl,
+                                     DS.getSourceRange().getBegin(),
+                                     FD.D, FD.BitfieldSize);
+        } else {
+          Field = Actions.ActOnField(CurScope, TagDecl,
+                                     DS.getSourceRange().getBegin(),
+                                     FD.D, FD.BitfieldSize);
+        }
         FieldDecls.push_back(Field);
       }
     } else { // Handle @defs
@@ -2016,6 +2025,8 @@ void Parser::ParseDeclarator(Declarator &D) {
 void Parser::ParseDeclaratorInternal(Declarator &D,
                                      DirectDeclParseFunction DirectDeclParser) {
 
+  if (Diags.hasAllExtensionsSilenced())
+    D.setExtension();
   // C++ member pointers start with a '::' or a nested-name.
   // Member pointers get special handling, since there's no place for the
   // scope spec in the generic path below.
diff --git a/clang/test/Sema/implicit-int.c b/clang/test/Sema/implicit-int.c
index 9eab953b3fc5..1a81cc55b583 100644
--- a/clang/test/Sema/implicit-int.c
+++ b/clang/test/Sema/implicit-int.c
@@ -24,7 +24,7 @@ h19_insline(n)  // expected-warning {{parameter 'n' was not declared, defaulting
 }
 
 struct foo {
- __extension__ __attribute__((packed)) x : 4; // expected-warning {{type specifier missing, defaults to 'int'}}
+ __extension__ __attribute__((packed)) x : 4;
 };