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, 57 insertions, 17 deletions

diff --git a/contrib/llvm/tools/clang/lib/Sema/SemaChecking.cpp b/contrib/llvm/tools/clang/lib/Sema/SemaChecking.cpp
index 24cdaef..3ffa748 100644
--- a/contrib/llvm/tools/clang/lib/Sema/SemaChecking.cpp
+++ b/contrib/llvm/tools/clang/lib/Sema/SemaChecking.cpp
@@ -66,6 +66,26 @@ bool Sema::CheckablePrintfAttr(const FormatAttr *Format, CallExpr *TheCall) {
   return false;
 }
 
+/// Checks that a call expression's argument count is the desired number.
+/// This is useful when doing custom type-checking.  Returns true on error.
+static bool checkArgCount(Sema &S, CallExpr *call, unsigned desiredArgCount) {
+  unsigned argCount = call->getNumArgs();
+  if (argCount == desiredArgCount) return false;
+
+  if (argCount < desiredArgCount)
+    return S.Diag(call->getLocEnd(), diag::err_typecheck_call_too_few_args)
+        << 0 /*function call*/ << desiredArgCount << argCount
+        << call->getSourceRange();
+
+  // Highlight all the excess arguments.
+  SourceRange range(call->getArg(desiredArgCount)->getLocStart(),
+                    call->getArg(argCount - 1)->getLocEnd());
+    
+  return S.Diag(range.getBegin(), diag::err_typecheck_call_too_many_args)
+    << 0 /*function call*/ << desiredArgCount << argCount
+    << call->getArg(1)->getSourceRange();
+}
+
 ExprResult
 Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
   ExprResult TheCallResult(Owned(TheCall));
@@ -137,15 +157,14 @@ Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
     if (SemaBuiltinLongjmp(TheCall))
       return ExprError();
     break;
+
+  case Builtin::BI__builtin_classify_type:
+    if (checkArgCount(*this, TheCall, 1)) return true;
+    TheCall->setType(Context.IntTy);
+    break;
   case Builtin::BI__builtin_constant_p:
-    if (TheCall->getNumArgs() == 0)
-      return Diag(TheCall->getLocEnd(), diag::err_typecheck_call_too_few_args)
-        << 0 /*function call*/ << 1 << 0 << TheCall->getSourceRange();
-    if (TheCall->getNumArgs() > 1)
-      return Diag(TheCall->getArg(1)->getLocStart(),
-                  diag::err_typecheck_call_too_many_args)
-        << 0 /*function call*/ << 1 << TheCall->getNumArgs()
-        << TheCall->getArg(1)->getSourceRange();
+    if (checkArgCount(*this, TheCall, 1)) return true;
+    TheCall->setType(Context.IntTy);
     break;
   case Builtin::BI__sync_fetch_and_add:
   case Builtin::BI__sync_fetch_and_sub:
@@ -875,7 +894,7 @@ bool Sema::SemaBuiltinLongjmp(CallExpr *TheCall) {
   return false;
 }
 
-// Handle i > 1 ? "x" : "y", recursivelly
+// Handle i > 1 ? "x" : "y", recursively.
 bool Sema::SemaCheckStringLiteral(const Expr *E, const CallExpr *TheCall,
                                   bool HasVAListArg,
                                   unsigned format_idx, unsigned firstDataArg,
@@ -918,6 +937,12 @@ bool Sema::SemaCheckStringLiteral(const Expr *E, const CallExpr *TheCall,
     }
     return false;
 
+  case Stmt::PredefinedExprClass:
+    // While __func__, etc., are technically not string literals, they
+    // cannot contain format specifiers and thus are not a security
+    // liability.
+    return true;
+      
   case Stmt::DeclRefExprClass: {
     const DeclRefExpr *DR = cast<DeclRefExpr>(E);
 
@@ -2896,6 +2921,17 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
     return DiagnoseImpCast(S, E, T, CC, DiagID);
   }
 
+  // Diagnose conversions between different enumeration types.
+  if (const EnumType *SourceEnum = Source->getAs<EnumType>())
+    if (const EnumType *TargetEnum = Target->getAs<EnumType>())
+      if ((SourceEnum->getDecl()->getIdentifier() || 
+           SourceEnum->getDecl()->getTypedefForAnonDecl()) &&
+          (TargetEnum->getDecl()->getIdentifier() ||
+           TargetEnum->getDecl()->getTypedefForAnonDecl()) &&
+          SourceEnum != TargetEnum)
+        return DiagnoseImpCast(S, E, T, CC, 
+                               diag::warn_impcast_different_enum_types);
+  
   return;
 }
 
@@ -3147,7 +3183,7 @@ void Sema::CheckArrayAccess(const clang::ArraySubscriptExpr *E) {
   if (!IndexExpr->isIntegerConstantExpr(index, Context))
     return;
 
-  if (!index.isNegative()) {
+  if (index.isUnsigned() || !index.isNegative()) {
     llvm::APInt size = ArrayTy->getSize();
     if (!size.isStrictlyPositive())
       return;
@@ -3159,12 +3195,15 @@ void Sema::CheckArrayAccess(const clang::ArraySubscriptExpr *E) {
     if (index.slt(size))
       return;
 
-    Diag(E->getBase()->getLocStart(), diag::warn_array_index_exceeds_bounds)
-      << index.toString(10, true) << size.toString(10, true)
-      << IndexExpr->getSourceRange();
+    DiagRuntimeBehavior(E->getBase()->getLocStart(), BaseExpr,
+                        PDiag(diag::warn_array_index_exceeds_bounds)
+                        << index.toString(10, true) << size.toString(10, true)
+                        << IndexExpr->getSourceRange());
   } else {
-    Diag(E->getBase()->getLocStart(), diag::warn_array_index_precedes_bounds)
-      << index.toString(10, true) << IndexExpr->getSourceRange();
+    DiagRuntimeBehavior(E->getBase()->getLocStart(), BaseExpr,
+                        PDiag(diag::warn_array_index_precedes_bounds)
+                          << index.toString(10, true)
+                          << IndexExpr->getSourceRange());
   }
 
   const NamedDecl *ND = NULL;
@@ -3173,7 +3212,8 @@ void Sema::CheckArrayAccess(const clang::ArraySubscriptExpr *E) {
   if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr))
     ND = dyn_cast<NamedDecl>(ME->getMemberDecl());
   if (ND)
-    Diag(ND->getLocStart(), diag::note_array_index_out_of_bounds)
-      << ND->getDeclName();
+    DiagRuntimeBehavior(ND->getLocStart(), BaseExpr,
+                        PDiag(diag::note_array_index_out_of_bounds)
+                          << ND->getDeclName());
 }