[Bug bootstrap/37330] New: mpfr & 32/64 multilib issue

[Bug bootstrap/37330] New: mpfr & 32/64 multilib issue

[olivier dot raoult at st dot com]

Hi,

My mpfr and gmp 32/64 bits libraries are installed respectively in $PREFIX/lib
and $PREFIX/lib64.
'configure' is called as following:
  configure .. --with-gmp-lib=$PREFIX/lib --with-mpfr-lib=$PREFIX/lib ...
It produces a Makefile with the following line:
  HOST_GMPLIBS = -L$PREFIX/lib -L$PREFIX/lib -lmpfr -lgmp
As far as I can see, there is no specific management of multilib context and
'make bootstrap' fails on mpfr link error.

As a workaround, I used the 64bits path for gmp and the 32bits path for mpfr:
  configure .. --with-gmp-lib=$PREFIX/lib64 --with-mpfr-lib=$PREFIX/lib ...
The Makefile line becomes:
  HOST_GMPLIBS = -L$PREFIX/lib64 -L$PREFIX/lib -lmpfr -lgmp
Then it works, even on a full 32 bits context (ie. i686-unknown-pc-linux) but
it's ugly, doesn't it? ;-)

Rgds,
  Olivier


-- 
           Summary: mpfr & 32/64 multilib issue
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: olivier dot raoult at st dot com
 GCC build triplet: x86_64-unknown-linux-gnu (RedHat 3/4)
  GCC host triplet: x86_64-unknown-linux-gnu (RedHat 3/4)
GCC target triplet: x86_64-unknown-linux-gnu (RedHat 3/4)


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37330

[Bug bootstrap/37330] mpfr & 32/64 multilib issue

[schwab at suse dot de]

------- Comment #1 from schwab at suse dot de  2008-09-02 13:51 -------
Why do you need two flavors?  The mfpr/gmp libraries are only used for the
compiler which is only built in one flavor.  If you are building for x86-64 you
should configure with $PREFIX/lib64 for both library directories.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37330

[Bug bootstrap/37330] mpfr & 32/64 multilib issue

[olivier dot raoult at st dot com]

------- Comment #2 from olivier dot raoult at st dot com  2008-09-02 14:12 -------
Hmm.. maybe! I tried to script a gcc builder program which shall work on i686,
and on x86_64. Then, for the second, it shall support native 64 and -m32 modes.

As libmpfr and libmgp appear as dynamic libraries, I assumed they will be used
... but 'ldd g++' doesn't confirm. So, the only thing I have to do is to use
-with-..-lib=$PREFIX/lib64 on x86_64 machines and -with-..-lib=$PREFIX/lib on
i686?!? Good!

If it works, it's a non-bug :( .. Sorry and thanks!


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37330

[Bug bootstrap/37330] mpfr & 32/64 multilib issue

[brian at dessent dot net]

------- Comment #3 from brian at dessent dot net  2008-09-02 17:36 -------
Subject: Re:  mpfr & 32/64 multilib issue


g++ (and gcc, gfortran, etc.) are just driver programs that invoke other
programs, they don't use these libraries.  You need to look at cc1 (or
cc1plus, f951, etc.) to see the dependency on these libraries.  You can
use e.g. "ldd $(gcc -print-prog-name=cc1)" to get the path to them
programatically.

As pointed out already gmp and mpfr are *host* libraries not *target*
libraries.  Even when gcc is built in a multilib configuration
supporting several targets there is still only a single host compiler,
and thus you need to specify the gmp and mpfr appropriate for the host.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37330

[Bug bootstrap/37330] mpfr & 32/64 multilib issue

[olivier dot raoult at st dot com]

------- Comment #4 from olivier dot raoult at st dot com  2008-09-03 14:04 -------
Verstehen! Thanks!


-- 

olivier dot raoult at st dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37330