Work around segfault calling error callback. See #14

src/python/ttfautohint/__init__.py

@@ -8,6 +8,7 @@
 from io import open
 import sys
 import os
+import platform
 
 from ttfautohint._version import __version__
 from ttfautohint import memory
@@ -100,6 +101,10 @@ def ttfautohint(self, **kwargs):
         out_buffer_p = POINTER(c_char)()
         out_buffer_len = c_size_t(0)
 
+        # For some reason the error callback causes a segfault on M1. See #14
+        if platform.system() == "Darwin" and platform.processor() == "arm64":
+            error_callback = None
+
         option_keys, option_values = format_varargs(
             out_buffer=byref(out_buffer_p),
             out_buffer_len=byref(out_buffer_len),