Fixes warnings emitted by Visual Studio 2010 compiler.

Patch by Erik Olofsson!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126796 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 8af07c7..de53494 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -274,8 +274,8 @@
     if (is64Bit())
       Write32(0); // reserved3
 
-    assert(OS.tell() - Start == is64Bit() ? macho::Section64Size :
-           macho::Section32Size);
+    assert(OS.tell() - Start == (is64Bit() ? macho::Section64Size :
+           macho::Section32Size));
   }
 
   void WriteSymtabLoadCommand(uint32_t SymbolOffset, uint32_t NumSymbols,