Objects/typeslots.inc is broken, and make stop on cygwin-1.7.35-i686. If built-in python is not found in make processing, Objects/typeslots.inc generating will fail. Because Objects/typeslots.inc is generated using $(PYTHON) in Makefile, but $(PYTHON) variable is a hard-coding value that isn't check a built-in python existent. make steps to fail and error message: $ ./configure --prefix=/opt/py34 $ touch Include/typeslots.h $ make ... python.exe ./Objects/typeslots.py < ./Include/typeslots.h > Objects/typeslots.inc /bin/sh: python.exe: command not found Makefile:851: recipe for target 'Objects/typeslots.inc' failed make: *** [Objects/typeslots.inc] Error 127 Cygwin python executable files: $ find /usr/bin/ -name 'python*.exe' /usr/bin/python2.7.exe /usr/bin/python3.2m.exe

I wrote the patch to replace $(PYTHON). Changes: Add TYPESLOTSGEN to configure.ac. TYPESLOTSGEN values is the built-in python. If the built-in python is not found, TYPESLOTSGEN echoes message that is skipping like ASDLGEN. Generated the configure script using autoreconf. Modify Makefile.pre.in to replace $(PYTHON) to $(TYPESLOTSGEN). And remove $(PYTHON) that isn't used anywhere. It seems already needless. Although I understand that the generated file touch can avoid to fail regenerate, I want to check built-in python to generate safer the Objects/typeslots.inc.

Sorry nobody acted on your patch earlier. This is the same as Issue 26662, which has a more general patch that does the same sort of thing.