[Mesa-dev] [PATCH] Revert "configure: ask vdpau.pc for the default location of the vdpau drivers"

[Ilia Mirkin]

On Sun, Sep 28, 2014 at 1:35 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> On 28/09/14 18:00, Ilia Mirkin wrote:
>> This reverts commit bbe6f7f865cd4316b5f885507ee0b128a20686eb.
>>
>> This change broke the usual assumption that setting a prefix will cause
>> files to be installed into that prefix. Restore that assumption before
>> people's system installs are accidentally overwritten, and everyone
>> starts having to add a --with-libvdpau-dir as a hack to work around this.
>>
> That assumption was broken long time ago. Mesa is _not_ the only package
> to do so.

I honestly can't think of another package that uses autoconf and
doesn't respect --prefix. You may be right that such a package may
exist, but if you point it out, I'll just file a bug with them asking
them to fix it :)

> Additionally the change is documented, and if no-one is bothered with
> check it's their own problem as things break. We all have assumptions,
> but we occasionally check if they are correct.
>
>> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
>> Cc: Christian König <deathsimple at vodafone.de>
>> Cc: Alexandre Demers <alexandre.f.demers at gmail.com>
>> Cc: Matt Turner <mattst88 at gmail.com>
>> Cc: Emil Velikov <emil.l.velikov at gmail.com>
>> ---
>>
>> Emil and I had a discussion about this on IRC but he didn't seem to
>> agree. However I think that this behavior is as broken as opening up
>> ld.so.conf, grabbing the first dir from that and using that as the
>> installation libdir. (Which I think everyone can agree is ridiculous.)
>>
> Indeed the ld.so.conf example is ridiculous, but this is a completely
> different thing. Those backends are used by the libvdapu library, thus
> one must adhere with it - i.e. the variable in pkg-config.
>
>> Setting a prefix should cause things to be installed into that prefix. This is
>> how every other autoconf-using package behaves.
>>
> I seriously doubt that you've been through every autoconf-using package
> so your last statement is full of air.

Certainly not every, you're right. However I did, for a fairly long
time, build all of my system packages by hand, so I have a pretty good
idea of how most of the software I've ever used builds. (Or at least
how it built back when I did that.)

>
>> As a side-note, using --with-module-dir as an installation destination is a
>> little crazy, but... I don't have the energy to fight that one.
>>
> Blame that one on the libvdpau people. They chose to expose this feature
> to the user.

Blame how libvdpau works? Sure. I think it's odd, but... I kinda see
why they did it that way.

This, however, has nothing to do with mesa. When I set --prefix,
that's saying "hey, install here". Not "hey, install here for most
things, but actually overwrite my system install for other things".

Something else to think about -- not everyone building mesa plans to
use the resulting libvdpau_$driver.so, however they might not build
with --disable-vdpau. But they do expect the GL install to go into
their prefix. Since vdpau is on by default, they'll get a failure on
make install if they're not root, or worse, overwrite their system
install if they carelessly run "sudo make install" or equivalent.

  -ilia

>
> Thanks
> Emil
>>  configure.ac | 11 +++--------
>>  1 file changed, 3 insertions(+), 8 deletions(-)
>>
>> diff --git a/configure.ac b/configure.ac
>> index 51f6c66..84af6b4 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -1768,17 +1768,12 @@ if test "x$enable_gallium_tests" = xyes; then
>>  fi
>>  AM_CONDITIONAL(HAVE_GALLIUM_TESTS, test "x$enable_gallium_tests" = xyes)
>>
>> -VDPAU_LIB_INSTALL_DIR_DEFAULT=''
>> -if test "x$enable_vdpau" = xyes; then
>> -    VDPAU_LIB_INSTALL_DIR_DEFAULT=`$PKG_CONFIG --variable=moduledir vdpau`
>> -fi
>> -
>>  dnl Directory for VDPAU libs
>>  AC_ARG_WITH([vdpau-libdir],
>>      [AS_HELP_STRING([--with-vdpau-libdir=DIR],
>> -        [directory for the VDPAU libraries @<:@default=`pkg-config --variable=moduledir vdpau`@:>@])],
>> +        [directory for the VDPAU libraries @<:@default=${libdir}/vdpau@:>@])],
>>      [VDPAU_LIB_INSTALL_DIR="$withval"],
>> -    [VDPAU_LIB_INSTALL_DIR="$VDPAU_LIB_INSTALL_DIR_DEFAULT"])
>> +    [VDPAU_LIB_INSTALL_DIR='${libdir}/vdpau'])
>>  AC_SUBST([VDPAU_LIB_INSTALL_DIR])
>>
>>  OMX_LIB_INSTALL_DIR_DEFAULT=''
>> @@ -1788,7 +1783,7 @@ fi
>>
>>  AC_ARG_WITH([omx-libdir],
>>      [AS_HELP_STRING([--with-omx-libdir=DIR],
>> -        [directory for the OMX libraries @<:@default=`pkg-config --variable=pluginsdir libomxil-bellagio`@:>@])],
>> +        [directory for the OMX libraries])],
>>      [OMX_LIB_INSTALL_DIR="$withval"],
>>      [OMX_LIB_INSTALL_DIR="$OMX_LIB_INSTALL_DIR_DEFAULT"])
>>  AC_SUBST([OMX_LIB_INSTALL_DIR])
>>
>