Error compilation for Windows x64 using MingGW 64

[Arritmic]

gemmlowp/internal/platform.h

Line 75 in dec2b7d

wintime -= 116444736000000000i64; // 1jan1601 to 1jan1970

When I try to compile with MinGW 64 bit it fails here. I understand that i64 is a Microsoft-specific suffix. Could it be replaced by a more standard version compatible with MVSC compiler and MinGW??

I think that for that function a "wintime -= 116444736000000000LL" would be ok?

[bjacob]

Good idea!