Fix path to OSX SDK with XCode >=4.3
Fix visual studio project xml file
Don't use long for pointers on 64-bit system

long may be 64 bit or 32 bit. On systems like Windows it is 32 bit and
therefore it cannot be used to store pointers.

The usage of intptr_t/uintptr_t should be evaluated to keep the code slightly
cleaner.
Disable PIC on MinGW to reduce warnings
Link against pthreads on MinGW for localtime_r emulation
Fix long usage in rjump implementation of x86_64