Silence VC++ warnings, patch by Hartmut Kaiser


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41693 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Lex/PPExpressions.cpp b/Lex/PPExpressions.cpp
index 48ec52a..2a18cfd 100644
--- a/Lex/PPExpressions.cpp
+++ b/Lex/PPExpressions.cpp
@@ -475,7 +475,7 @@
       break;
     case tok::lessless: {
       // Determine whether overflow is about to happen.
-      unsigned ShAmt = RHS.getLimitedValue();
+      unsigned ShAmt = static_cast<unsigned>(RHS.getLimitedValue());
       if (ShAmt >= LHS.getBitWidth())
         Overflow = true, ShAmt = LHS.getBitWidth()-1;
       else if (LHS.isUnsigned())
@@ -490,7 +490,7 @@
     }
     case tok::greatergreater: {
       // Determine whether overflow is about to happen.
-      unsigned ShAmt = RHS.getLimitedValue();
+      unsigned ShAmt = static_cast<unsigned>(RHS.getLimitedValue());
       if (ShAmt >= LHS.getBitWidth())
         Overflow = true, ShAmt = LHS.getBitWidth()-1;
       Res = LHS >> ShAmt;