MBEDTLS_FS_IO is commented out, but still getting unresolved references to FS functions

I have commented out the MBEDTLS_FS_IO #define, yet I’m still getting unresolved references to _write, _close, _fstat, _isatty, _lseek and _read at link time. I was also getting an unresolved reference to gettimeofday, but when I commented out MBEDTLS_HAVE_TIME and MBEDTLS_HAVE_TIME_DATE, that particular unresolved symbol went away. I’m not sure what I’m missing here. According to the documentation, // #define MBEDTLS_FS_IO should do it. Any ideas?

Disabling MBEDTLS_SELF_TEST seems to have fixed the problem.