Add -Wimplicit-fallthrough warning flag, which warns on fallthrough between

cases in switch statements. Also add a [[clang::fallthrough]] attribute, which
can be used to suppress the warning in the case of intentional fallthrough.

Patch by Alexander Kornienko!

The handling of C++11 attribute namespaces in this patch is temporary, and will
be replaced with a cleaner mechanism in a subsequent patch.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156086 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 1 deletions

diff --git a/lib/Sema/AttributeList.cpp b/lib/Sema/AttributeList.cpp
index 101e0384fa..8e7029350a 100644
--- a/lib/Sema/AttributeList.cpp
+++ b/lib/Sema/AttributeList.cpp
@@ -15,6 +15,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/Basic/IdentifierTable.h"
 #include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/SmallString.h"
 using namespace clang;
 
 size_t AttributeList::allocated_size() const {
@@ -99,7 +100,8 @@ AttributePool::createIntegerAttribute(ASTContext &C, IdentifierInfo *Name,
 
 #include "clang/Sema/AttrParsedAttrKinds.inc"
 
-AttributeList::Kind AttributeList::getKind(const IdentifierInfo *Name) {
+AttributeList::Kind AttributeList::getKind(const IdentifierInfo *Name,
+                                           const IdentifierInfo *ScopeName) {
   StringRef AttrName = Name->getName();
 
   // Normalize the attribute name, __foo__ becomes foo.
@@ -107,5 +109,10 @@ AttributeList::Kind AttributeList::getKind(const IdentifierInfo *Name) {
       AttrName.size() >= 4)
     AttrName = AttrName.substr(2, AttrName.size() - 4);
 
+  // FIXME: implement attribute namespacing correctly.
+  SmallString<64> Buf;
+  if (ScopeName)
+    AttrName = ((Buf += ScopeName->getName()) += "___") += AttrName;
+
   return ::getAttrKind(AttrName);
 }