Re: [dpdk-dev] [PATCH] mk: add makefile extention support

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2016-03-03 14:55, Wiles, Keith:
> >>2016-02-28 21:47, Wiles, Keith:
> >>> >Hi,
> >>> >
> >>> >2016-02-09 11:35, Keith Wiles:
> >>> >> Adding support to the build system to allow for Makefile.XXX
> >>> >> extention to a subtree, which already has Makefiles. These
> >>> >> Makefiles could be from the autotools and others places. Using
> >>> >> the Makefile extention RTE_MKFILE_SUFFIX in a makefile subtree
> >>> >> using 'export RTE_MKFILE_SUFFIX=.XXX' to use Makefile.XXX in
> >>> >> that subtree.
> >>> >> 
> >>> >> The main reason I needed this feature was to integrate a autotool
> >>> >> open source projects with DPDK and keep the original Makefiles.
> >>> >
> >>> >Sorry I fail to understand why it is needed.
> >>> >Are you trying to add autotool in DPDK? I don't think it is a good approach.
> >>> >The DPDK must provide a pkgconfig interface to be integrated anywhere.
> >>> 
> >>> I was not trying to add autotools to DPDK. On a number of times I wanted to integrate a open source project(s) with DPDK and use DPDK’s build system, but because the open source project already contained Makefile files you can not use DPDK build system without modify or moving the original Makefile files. Using this method I can just add a exported variable and supply my own Makefile.XXX files.
> >>> 
> >>> One case was building FreeBSD source, but I did not want to modify FreeBSD Makefiles (or reply on previous built Makefiles as they would not work on Linux anyway) as I was pulling the source down from freebsd.org repo. Using a patch to add the Makefiles with a different suffix allows me to build FreeBSD using DPDK, without having to modify or own the FreeBSD source. I have had this problem a number of times with open source code I did not want to modify, but just build within DPDK build system and adding the support for a different suffix to DPDK provided a clean way. The change does not effect the correct build system and just allows someone to define a new suffix for a given subtree in the code.
> >>
> >>Why would you like to have another project inside the DPDK files tree?
> >>If you want to integrate the lib inside an existing project, the solution
> >>is pkgconfig.
> >
> >The goal for me was to use DPDK build system for that project, instead of using autotools or some other makefile system. In the case of FreeBSD code, the FreeBSD build system requires FreeBSD tools to be built as the ‘make’ and the Makefiles are very different on a Linux machine.
> 
> Does anyone find this patch useful, I would hate to see this one die as it does not effect the current builds, but adds support for using DPDK build system without having to modify or move the existing Makefiles.

I would hate making the build system even more complicated to use it
for something which is not its role.
It opens the door to feature requests which are clearly out of its scope.