Update llvm/clang to trunk r126547.

There are several bugfixes in this update, but the most important one is
to ensure __start_ and __stop_ symbols for linker sets and kernel module
metadata are always emitted in object files:

  http://llvm.org/bugs/show_bug.cgi?id=9292

Before this fix, if you compiled kernel modules with clang, they would
not be properly processed by kldxref, and if they had any dependencies,
the kernel would fail to load those.  Another problem occurred when
attempting to mount a tmpfs filesystem, which would result in 'operation
not supported by device'.

1 files changed, 11 insertions, 20 deletions

diff --git a/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/PointerSubChecker.cpp b/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/PointerSubChecker.cpp
index f28fe9a..bf85b95 100644
--- a/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/PointerSubChecker.cpp
+++ b/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/PointerSubChecker.cpp
@@ -14,31 +14,26 @@
 //===----------------------------------------------------------------------===//
 
 #include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/CheckerV2.h"
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
-#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerVisitor.h"
 
 using namespace clang;
 using namespace ento;
 
 namespace {
 class PointerSubChecker 
-  : public CheckerVisitor<PointerSubChecker> {
-  BuiltinBug *BT;
+  : public CheckerV2< check::PreStmt<BinaryOperator> > {
+  mutable llvm::OwningPtr<BuiltinBug> BT;
+
 public:
-  PointerSubChecker() : BT(0) {}
-  static void *getTag();
-  void PreVisitBinaryOperator(CheckerContext &C, const BinaryOperator *B);
+  void checkPreStmt(const BinaryOperator *B, CheckerContext &C) const;
 };
 }
 
-void *PointerSubChecker::getTag() {
-  static int x;
-  return &x;
-}
-
-void PointerSubChecker::PreVisitBinaryOperator(CheckerContext &C,
-                                               const BinaryOperator *B) {
+void PointerSubChecker::checkPreStmt(const BinaryOperator *B,
+                                     CheckerContext &C) const {
   // When doing pointer subtraction, if the two pointers do not point to the
   // same memory chunk, emit a warning.
   if (B->getOpcode() != BO_Sub)
@@ -66,19 +61,15 @@ void PointerSubChecker::PreVisitBinaryOperator(CheckerContext &C,
 
   if (ExplodedNode *N = C.generateNode()) {
     if (!BT)
-      BT = new BuiltinBug("Pointer subtraction", 
+      BT.reset(new BuiltinBug("Pointer subtraction", 
                           "Subtraction of two pointers that do not point to "
-                          "the same memory chunk may cause incorrect result.");
+                          "the same memory chunk may cause incorrect result."));
     RangedBugReport *R = new RangedBugReport(*BT, BT->getDescription(), N);
     R->addRange(B->getSourceRange());
     C.EmitReport(R);
   }
 }
 
-static void RegisterPointerSubChecker(ExprEngine &Eng) {
-  Eng.registerCheck(new PointerSubChecker());
-}
-
 void ento::registerPointerSubChecker(CheckerManager &mgr) {
-  mgr.addCheckerRegisterFunction(RegisterPointerSubChecker);
+  mgr.registerChecker<PointerSubChecker>();
 }