[FFmpeg-cvslog] r14143 - in trunk: common.mak configure

[Måns Rullgård]

Diego Biurrun <diego at biurrun.de> writes:

> On Sat, Jul 12, 2008 at 05:01:54PM +0100, M?ns Rullg?rd wrote:
>> Diego Biurrun <diego at biurrun.de> writes:
>> 
>> > On Wed, Jul 09, 2008 at 09:09:51PM +0200, mru wrote:
>> >> 
>> >> Log:
>> >> regenerate dependencies when building object files
>> >
>> > Hmm...
>> >
>> >> --- trunk/common.mak	(original)
>> >> +++ trunk/common.mak	Wed Jul  9 21:09:50 2008
>> >> @@ -38,6 +38,8 @@ CFLAGS := -DHAVE_AV_CONFIG_H -D_FILE_OFF
>> >>  
>> >> +%.o: %.d
>> >> +
>> >> 
>> >> --- trunk/configure	(original)
>> >> +++ trunk/configure	Wed Jul  9 21:09:50 2008
>> >> @@ -970,7 +970,7 @@ SLIBNAME_WITH_MAJOR='$(SLIBNAME).$(LIBMA
>> >>  
>> >>  # gcc stupidly only outputs the basename of targets with -MM
>> >> -DEPEND_CMD='$(CC) $(CFLAGS) -MM -MG $< | sed -e "/^\#.*/d" -e "1s,^,$(@D)/," -e "s,\\([[:space:]]\\)\\(version\\.h\\),\\1\$$(BUILD_ROOT_REL)/\\2," -e "s/\(.*\)\.o/\1.d &/"'
>> >> +DEPEND_CMD='$(CC) $(CFLAGS) -MM -MG $< | sed -e "/^\#.*/d" -e "1s,^,$(@D)/," -e "s,\\([[:space:]]\\)\\(version\\.h\\),\\1\$$(BUILD_ROOT_REL)/\\2,"'
>> >
>> > Uoti just confirmed my initial suspicion after I ported this over
>> > to MPlayer: This change is not equivalent.
>> >
>> > The reason I made this change in the first place was to have .d files
>> > updated when any of the files the .c file depends on changes.  This was
>> > to reflect changing header inclusions, etc.  This no longer works.  Try
>> > touching a header file and running make, .d files will not get updated
>> > even though they could be affected.
>> 
>> I realised this later.  The problem is that, as it was, removing a
>> header file totally confused make into not even trying rebuild the
>> object file, and people were complaining about that.
>
> Elaborate, what scenario exactly is causing problems?

Delete any header file, and try to make an object file that depends on
it.

-- 
M?ns Rullg?rd
mans at mansr.com