Fixes for re-enabling more MSVC level 4 warnings: courgette/ edition

courgette/disassembler_elf_32.h

Index: courgette/disassembler_elf_32.h
diff --git a/courgette/disassembler_elf_32.h b/courgette/disassembler_elf_32.h
index dc44ec5edcf395897a55d0a3abeac01e757abe8c..58e2eba614c09e7862755556e633971a3c6bf80c 100644
--- a/courgette/disassembler_elf_32.h
+++ b/courgette/disassembler_elf_32.h
@@ -30,7 +30,7 @@ class DisassemblerElf32 : public Disassembler {
   // class encapsulates this behavior.  public for use in unit tests.
   class TypedRVA {
    public:
-    explicit TypedRVA(RVA rva) : rva_(rva), offset_(-1) {
+    explicit TypedRVA(RVA rva) : rva_(rva), offset_(static_cast<size_t>(-1)) {
     }
 
     virtual ~TypedRVA() { };