Re: [Notion-devel] Another obscure build peculiarity (in libextl this time)

[Ole J. B. <ole...@ya...>]

Agreed, an extra sed can't be that bad? (to the extend that anything needs to be done)

Hopefully my next inquiry will be of a less nitpicking character ;)


On Wed, 16 Feb 2011 00:07:29 +0100, Arnout Engelen <no...@bz...> wrote:

> Hi,
>
> I can confirm the issue.
>
> Adding *.mk to the dependencies seems a bit odd, as basically everything is
> dependent on those and it's uncommon to list them as dependencies.
>
> Adding libextrl-mkexports to the 'clean' list seems like a bad idea: afaics the
> convention is that 'make clean' will not clean the 'deliverables': in principle
> you should be able to 'make install' even after having done 'make clean'.
>
> A third option might be to specify that libextrl-mkexports always needs to be
> rebuilt, regardless of whether its dependencies have changed. This can be done
> by:
>
> .PHONY : libextrl-mkexports
>
> This might be a GNU thing, but we're GNU Make-specific anyway.
>
> Thoughts?
>
>
> Kind regards,
>
> Arnout
>
> On Tue, Feb 15, 2011 at 10:39:06PM +0100, Ole Jørgen Brønner wrote:
>> If you do a 'make -j2' first, and for some weird reason do a 'make -j2' again, realize you have to change the lua settings in system.mk, do a 'make clean', and then 'make -j2' again, the changes has not propagated to the shebang in 'libextl-mkexports'.
>>
>> or maybe better:
>>
>> # make sure lua config is wrong
>> make realclean
>> make -j2
>> make -j2
>> # check that libextl-mkexports has appeared
>> # fix lua config
>> make clean
>> make
>> make install
>> # -> libextl-mkexports fails to run. (wrong shebang)
>>
>> This only happens when running 'make -j2'. For some reason you have to run it twice to get the effect, although that could be coincidence related to scheduling?
>>
>> The reason is that 'make clean' does not remove 'libextl-mkexports', and the source ('libextl-mkexports.in') contains a "macro", expanded by the makefile:
>>
>>    libextl-mkexports: libextl-mkexports.in
>>    	sed "1s:LUA50:$(LUA):" $< > $@
>>
>> 'libextl-mkexports' is thus not remade, and the shebang remains unchanged. You wont realize the error until you try to run 'libextl-mkexports' (ie. when building notion/ion3), since the build succeeds.
>>
>> 'make realclean' removes the file, but it's not exactly obvious...
>>
>> Again.. a fairly obscure(*) problem ;)
>>
>> (*) Apart from the 'make -j2', and for some reason running make twice, I think you'd only see this when you change your lua install location. eg. from the deb package to upstream.
>>
>> Easiest fix (if deemed worthwhile) is either to add the *.mk files as dependencies to the 'libextl-mkexports' target, or add 'libextrl-mkexports' to the clean list. (line 136 in 'build/rules.mk'). (Well, according to my limited make knowledge at least)
>>
>> - Ole Jørgen Brnner