Build fails on windows with VS 2015

[rjgotten]

Building this library via the NodeJS wrapper module node-sfnt2woff-zopfli configured for VS 2015 Update 3 gives an error regarding a redefinition of int8_t and different basic types.

Visual Studio defines int8_t and other inttypes since VS 2010, where they're available in stdint.h. Compilation fails because the compiler is being pedantic about a type mismatch with those standard headers.

You should either expand the #ifdef _MSC_VER check to handle compatible versions, or you should ensure that the redefinition is type-compatible. Adding an explicit signed to the redefinitions of int8_t; int16_t and int32_t might fix this, but the better method is probably to use what's there.

I.e. with MS compilers, import Microsoft's standard implementation if it is known to exist; otherwise rely on the older non-standard definitions for __int8 and similar. E.g.

#ifdef _MSC_VER
    #if _MSC_VER >= 1600
        #include <stdint>
    #else
        typedef __int8              int8_t;
        typedef __int16             int16_t;
        typedef __int32             int32_t;
        typedef __int64             int64_t;
        typedef unsigned __int8     uint8_t;
        typedef unsigned __int16    uint16_t;
        typedef unsigned __int32    uint32_t;
        typedef unsigned __int64    uint64_t;
    #endif
#endif