Building a subdirectory ignores parent subdir-ccflags (was: Re: [PATCH 1/2] staging: lustre: Add include path to Makefile)

Building a subdirectory ignores parent subdir-ccflags (was: Re: [PATCH 1/2] staging: lustre: Add include path to Makefile)

[Joe Perches]

On Mon, 2016-08-15 at 14:14 -0700, Joe Perches wrote:
> On Mon, 2016-08-15 at 23:04 +0200, Greg Kroah-Hartman wrote:
> > On Mon, Aug 15, 2016 at 12:33:23PM -0700, Joe Perches wrote:
> > > Start to rationalize include paths in source code files.
> []
> > > diff --git a/drivers/staging/lustre/Makefile b/drivers/staging/lustre/Makefile
> []
> > > @@ -1,2 +1,5 @@
> > > +subdir-ccflags-y += -I$(srctree)/drivers/staging/lustre/include/
> > > +subdir-ccflags-y += -I$(srctree)/drivers/staging/lustre/lustre/include/
> > > +
> > >  obj-$(CONFIG_LNET)		+= lnet/
> > >  obj-$(CONFIG_LUSTRE_FS)		+= lustre/
> > This is good, but does this break the subdir make command:
> > 	make M=drivers/staging/lustre/foo_dir/
> > ?
> hmm, yeah, it does.  Oh well, nevermind for awhile.
> > I remember the last time I tried to clean this up, it took a while...
> It seems like something the build tools should
> handle correctly now, but I'll look at it.

Perhaps making a specific directory should also walk up
any parent directory Makefiles looking for subdir flags.

Is that unreasonable?  Any suggestions?

Re: Building a subdirectory ignores parent subdir-ccflags

[Michal Marek]

Dne 15.8.2016 v 23:29 Joe Perches napsal(a):
> On Mon, 2016-08-15 at 14:14 -0700, Joe Perches wrote:
>> On Mon, 2016-08-15 at 23:04 +0200, Greg Kroah-Hartman wrote:
>>> On Mon, Aug 15, 2016 at 12:33:23PM -0700, Joe Perches wrote:
>>>> Start to rationalize include paths in source code files.
>> []
>>>> diff --git a/drivers/staging/lustre/Makefile b/drivers/staging/lustre/Makefile
>> []
>>>> @@ -1,2 +1,5 @@
>>>> +subdir-ccflags-y += -I$(srctree)/drivers/staging/lustre/include/
>>>> +subdir-ccflags-y += -I$(srctree)/drivers/staging/lustre/lustre/include/
>>>> +
>>>>  obj-$(CONFIG_LNET)		+= lnet/
>>>>  obj-$(CONFIG_LUSTRE_FS)		+= lustre/
>>> This is good, but does this break the subdir make command:
>>> 	make M=drivers/staging/lustre/foo_dir/
>>> ?
>> hmm, yeah, it does.  Oh well, nevermind for awhile.
>>> I remember the last time I tried to clean this up, it took a while...
>> It seems like something the build tools should
>> handle correctly now, but I'll look at it.
> 
> Perhaps making a specific directory should also walk up
> any parent directory Makefiles looking for subdir flags.
> 
> Is that unreasonable?  Any suggestions?

I suggest to do make drivers/staging/lustre/. If building the lustre
subdirectories is going to be a common use case, then you can propagate
the subdir-ccflags-y assignment down to the individual Makefiles.

Michal

Re: Building a subdirectory ignores parent subdir-ccflags

[Joe Perches]

On Tue, 2016-08-16 at 00:07 +0200, Michal Marek wrote:

Hi Michal.

> > Perhaps making a specific directory should also walk up
> > any parent directory Makefiles looking for subdir flags.
> > 
> > Is that unreasonable?  Any suggestions?
> I suggest to do make drivers/staging/lustre/. If building the lustre
> subdirectories is going to be a common use case, then you can propagate
> the subdir-ccflags-y assignment down to the individual Makefiles.

I don't have a problem with that.

Others might though for whatever reason.

There are a couple other places in the tree that
also use subdir-ccflags where the results of making
a subdirectory would either fail or have unexpected
results.

Does it matter?  Not much, but it could be nicer if
it's possible for parent Makefile paths to be ascended.

I'm not much of a Makefile person, but perhaps you have
some clues/tips/suggestions for implementation?