Re: GUB and mpfr/mpc

[David Kastrup]

"Phil Holmes" <address@hidden> writes:

> ----- Original Message ----- 
> From: "Phil Holmes" <address@hidden>
> To: "Federico Bruni" <address@hidden>
> Cc: <address@hidden>
> Sent: Saturday, October 25, 2014 3:39 PM
> Subject: Re: GUB and mpfr/mpc
>
>
>> It's my computer (or strictly, a VM on my computer).
>>
>> So it would appear that in order to use a current version of gcc, I
>> need at least 12.04 and I might as well go to 14.04 in order to
>> build GUB?
>>
>> --
>> Phil Holmes
>
> OK - I've downloaded 14.04, installed it in a VM, updated it,
> installed git, cloned GUB and run make bootstrap.  I get:
>
> building package: tools::librestrict
> *** Stage: download (librestrict, tools)
> *** Stage: untar (librestrict, tools)
> *** Stage: patch (librestrict, tools)
> *** Stage: shadow (librestrict, tools)
> *** Stage: compile (librestrict, tools)
> Command barfed: cd /home/gub/gub/target/tools/build/librestrict-1.9.a
> && gcc -W -Wall -fno-stack-protector -I. -fPIC -shared -o
> librestrict-stat.so restrict-stat.c || gcc -W -Wall -I. -fPIC -shared
> -o librestrict-stat.so restrict-stat.c
>
> Tail of target/tools/log/librestrict.log >>>>>>>>
> ./xstatconv.c:269:5: error: 'struct stat' has no member named '__unused5'
> buf->__unused5 = 0;
> ^
> Command barfed: cd /home/gub/gub/target/tools/build/librestrict-1.9.a
> && gcc -W -Wall -fno-stack-protector -I. -fPIC -shared -o
> librestrict-stat.so restrict-stat.c || gcc -W -Wall -I. -fPIC -shared
> -o librestrict-stat.so restrict-stat.c
> <<<<<<<< Tail of target/tools/log/librestrict.log
>
> *** Failed target: tools::librestrict
> make: *** [bootstrap-git] Error 1
>
> Anyone know why?

struct stat is defined in <sys/stat.h> (for example).  It does not
contain anything like __unused5 as far as I can see.  My guess would be
that this is defined in an alternative version in some header file of
restrict-stat.c and that this definition and the system definition get
mixed up, possibly by something else including the system definition via
some other means.

But I have, frankly, no idea what librestrict might be and what it is
used for.  So this is totally handwavy.

Actually, I read on <URL:http://lilypond.org/gub/basics>

    LIBRESTRICT

    A common problem with [making reproducible cross] builds is using
    files or features that are not controlled by the [GUB] build
    process, but just happen to be on the build host and happen to
    differ between most build hosts.

    GUB uses the LD_PRELOAD feature with the gub/specs/librestrict.py
    package and code from ./librestrict/restrict.c to disallow reading
    from build host files. This makes for much better reprocucibility,
    especially between different build hosts.

    The downside to this LIBRESTRICT feature is that quite a few
    packages are not prepared for cross building. LIBRESTRICT will catch
    these errors and they have to be fixed in the package's spec file.

    This is what such a LIBRESTRICT assertion could like

        
librestrict:error:/home/janneke/vc/gub/target/mingw/root/usr/cross/libexec/gcc/i686-mingw32/4.1.1/cc1plus:
 tried to open () file /home/janneke/vc/lilypond/lily/main.cc
        librestrict:allowed:
          /home/janneke/vc/gub/target/mingw
          /tmp
          /dev/null
          /dev/urandom
          /proc/self
        cc1plus: internal compiler error: Aborted
        Please submit a full bug report,
        with preprocessed source if appropriate.
        See  for instructions.
        [1]10:42:08 address@hidden:~/vc/gub
        $ 

    you often find these in config.log files when package-dependant code
    blondly looks in /usr/include or /usr/lib.

So it would appear that librestrict has been written by Jan.  The error
you see does not appear like a failure of librestrict (like described)
but rather a failure to build librestrict in the first place.

Jan?

-- 
David Kastrup