The file include\pyport.h in Python installation directory does not have #include < stdint.h > anymore. This leaves intmax_t undefined.
A workaround for Microsoft VC compiler is to force include stdint.h via OS environment variable CL:
- Open command prompt
- Setup VC environment by runing vcvars*.bat (choose file name depending on VC version and architecture)
- set CL=-FI”Full-Path\stdint.h” (use real value for Full-Path for the environment)
- pip install pycrypto