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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175006 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-objdump/llvm-objdump.cpp b/tools/llvm-objdump/llvm-objdump.cpp
index 95f7690..322bd21 100644
--- a/tools/llvm-objdump/llvm-objdump.cpp
+++ b/tools/llvm-objdump/llvm-objdump.cpp
@@ -481,7 +481,7 @@
       // Print ascii.
       outs() << "  ";
       for (std::size_t i = 0; i < 16 && addr + i < end; ++i) {
-        if (std::isprint(Contents[addr + i] & 0xFF))
+        if (std::isprint(static_cast<unsigned char>(Contents[addr + i]) & 0xFF))
           outs() << Contents[addr + i];
         else
           outs() << ".";