Add static cast to unsigned char whenever a character classification function is called with a signed char argument, in order to avoid assertions in Windows Debug configuration.

llvm-svn: 175006

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
index 8e2bbb79eeb..b73cd03ddd6 100644
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -130,12 +130,13 @@ static bool isValidName(StringRef MDName) {
   if (MDName.empty())
     return false;
 
-  if (!std::isalpha(MDName[0]))
+  if (!std::isalpha(static_cast<unsigned char>(MDName[0])))
     return false;
 
   for (StringRef::iterator I = MDName.begin() + 1, E = MDName.end(); I != E;
        ++I) {
-    if (!std::isalnum(*I) && *I != '_' && *I != '-' && *I != '.')
+    if (!std::isalnum(static_cast<unsigned char>(*I)) && *I != '_' &&
+        *I != '-' && *I != '.')
       return false;
   }
   return true;