Bug#613046: debian-policy: please update example in 4.9.1 (debian/rules and DEB_BUILD_OPTIONS)

[Raphael Hertzog <hertzog@debian.org>]

On Fri, 27 Jan 2012, Matthijs Kooijman wrote:
> > -ifneq (,$(filter noopt,$(DEB_BUILD_OPTIONS)))
> > -    CFLAGS += -O0
> > -else
> > -    CFLAGS += -O2
> > -endif
> > +CFLAGS := -Wall $(shell dpkg-buildflags --get CFLAGS)
> >  ifeq (,$(filter nostrip,$(DEB_BUILD_OPTIONS)))
> >      INSTALL_PROGRAM += -s
> >  endif
> 
> Wouldn't it be more appropriate to use
> 
>     DEB_CFLAGS_MAINT_PREPEND := -Wall
> 
> here before calling dpkg-buildflags? Possibly the rest of the example
> could be modified to use DEB_CFLAGS_MAINT_APPEND as well.

Well, they are there so that you can tweak the output of dpkg-buildflags
when the call happens in lower layer and that you have no control over the
call and its output.

And you must take care because $(shell dpkg-buildflags ...) will not see the
DEB_CFLAGS_MAINT_PREPEND that you have set in the rules files. Either you
do $(shell DEB_CFLAGS_MAINT_PREPEND=... dpkg-buildflags ...) or you use
/usr/share/dpkg/buildflags.mk which does the right thing for you.

> Not sure if this is really needed, but it seems to me that that is what
> these variables were invented for :-)

Maybe all the samples from Policy should be simplified to use the Makefile
snippets...

Cheers,
-- 
Raphaël Hertzog ◈ Debian Developer

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