[DVDnav-discuss] [PATCH] Fix parallel jobs; sources need version.h

[Nico Sabbi]

On Wednesday 30 April 2008 14:55:06 Dan Nicholson wrote:
> On Wed, Apr 30, 2008 at 12:57 AM, Nico Sabbi <Nicola.Sabbi at poste.it> 
wrote:
> > On Monday 28 April 2008 23:53:38 Dan Nicholson wrote:
> >  > ---
> >  >  Makefile |    2 ++
> >  >  1 files changed, 2 insertions(+), 0 deletions(-)
> >  >
> >  > diff --git a/Makefile b/Makefile
> >  > index fcc3940..85108e5 100644
> >  > --- a/Makefile
> >  > +++ b/Makefile
> >  > @@ -81,6 +81,8 @@ endif
> >  >  version.h:
> >  >       sh $(SRC_PATH)/version.sh $(SRC_PATH)
> >  >
> >  > +$(SRCS) $(DVDREAD_SRCS): version.h
> >  > +
> >  >
> >  >  # General targets
> >
> >  can you explain, please?
> >  If I read the dependencies all .c files already depend on
> > version.h
>
> They don't. The library $(SHLIB) depends on version.h. Since that's
> the first target, version.h gets built immediately. However, if you
> have multiple jobs (-j3 or whatever), make will also begin building
> the .c files without waiting for version.h to be built. This causes
> a race condition if any .c file including config.h or version.h is
> built before version.h is created.
>
> You can see if the .c files depend on version.h pretty easily. Run
> `make -d dvdnav.o' and redirect the log somewhere. It will show in
> detail the prerequisites for the target dvdnav.o. For me, version.h
> never comes up until after the patch above. If this is a clean
> checkout (i.e., you've only run configure2), `mkdir obj && make
> dvdnav.o' will bomb like this:
>
> cd obj && gcc -MD -g -O2 -march=i686 -pipe  -Wall -funsigned-char
> -I/home/dan/scm/libdvdnav -I"/home/dan/scm/libdvdnav"/src
> -I"/home/dan/scm/libdvdnav"/src/vm -DDVDNAV_COMPILE
> -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE -DHAVE_CONFIG_H
> -DHAVE_DLFCN_H -I"/home/dan/scm/libdvdnav"/src/dvdread -c -o
> dvdnav.o /home/dan/scm/libdvdnav/src/dvdnav.c
> In file included from /home/dan/scm/libdvdnav/src/dvdnav.c:25:
> /home/dan/scm/libdvdnav/config.h:2:21: error: version.h: No such
> file or directory
>
> With the patch, it properly generates version.h first, and this
> works.
>

ok and sorry for the delay: I've been busy all week. Today or tomorrow
I'll commit your patch(es)