Re: [PATCH] mingw: disable Python

[Junio C Hamano <gitster@pobox.com>]

Erik Faye-Lund <kusmabite@googlemail.com> writes:

>> On Fri, 8 Jan 2010, Johannes Sixt wrote:
>>
>>> Erik Faye-Lund schrieb:
>>> > Python is not commonly installed on Windows machines, so
>>> > we should disable it there by default.
>>> >
>>> > --- a/Makefile
>>> > +++ b/Makefile
>>> > @@ -1027,6 +1027,7 @@ ifneq (,$(findstring MINGW,$(uname_S)))
>>> > +   NO_PYTHON = YesPlease
>>>
>>> I'm worried that with this solution it is impossible to re-enable Python
>>> in config.mak (how do you undefine a Makefile variable?);
>
>> How about
>>
>>        NO_PYTHON=
>>
>> in config.mak?
>
> That doesn't work for me, at least not out of the box. NO_PYTHON is
> still defined, it's just defined to an empty string.

I think Dscho is right.  "ifdef FOO" yields (and should yield) false if
FOO is set to empty.

-- >8 -- cut here and try it for yourself -- >8 --
#!/bin/sh

rm -f config.mk

cat >Makefile <<\EOF
# The default is...
all::
FROTZ = NITFOL
-include config.mk
ifdef FROTZ
all::
	echo FROTZ is $(FROTZ)
else
all::
	echo FROTZ is not defined
endif
EOF

make
# says "NITFOL"

echo "FROTZ =" >config.mk
make
# says "not defined"

exit
-- 8< --