build now requires Python exist before the build starts

[Toon Knapen]

nnorwitz at gmail.com wrote:
> 
> It shouldn't actually be required.  I'm assuming the problem is while
> trying to run asdlgen.py.  The generated files are checked in, but the
> timestamps are wrong and the Makefile is trying to be helpful.
> 
> Try:
>   touch Include/Python-ast.h Python/Python-ast.c
>   make
> 


Thanks, indeed it is a timestamp problem. However I copied the error 
message 'build now requires Python exists before the build starts' 
directly from the Makefile. It might be instructive that the Makefile 
also mentions that this is not strictly necessary and documents that 
python is needed if one wants to regenerated Python-ast.[hc].

Thanks a lot,

toon