Improve unreachable code warnings for with respect to dead functional casts in C++.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94106 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/Stmt.h

@@ -24,7 +24,6 @@
 #include "llvm/ADT/SmallVector.h"
 #include "clang/AST/ASTContext.h"
 #include <string>
-#include <iterator>
 using llvm::dyn_cast_or_null;
 
 namespace llvm {

lib/Sema/SemaChecking.cpp

@@ -2121,6 +2121,11 @@ static SourceLocation GetUnreachableLoc(CFGBlock &b, SourceRange &R1,
     R1 = CSC->getSubExpr()->getSourceRange();
     return CSC->getLParenLoc();
   }
+  case Expr::CXXFunctionalCastExprClass: {
+    const CXXFunctionalCastExpr *CE = cast <CXXFunctionalCastExpr>(S);
+    R1 = CE->getSubExpr()->getSourceRange();
+    return CE->getTypeBeginLoc();
+  }
   case Expr::ImplicitCastExprClass:
     ++sn;
     goto top;

test/SemaCXX/warn-unreachable.cpp

@@ -40,6 +40,9 @@ void test3() {
   halt()
     --;         // expected-warning {{will never be executed}}
   halt()
-    ?         // expected-warning {{will never be executed}}
+    ?           // expected-warning {{will never be executed}}
     dead() : dead();
+  live(),
+    float       // expected-warning {{will never be executed}}
+      (halt());
 }