> The problem with py-numpy is rtld is responsible for parsing DT_RPATH
> python does not have a DT_RPATH for our gfortran libs so it never gets
+preloaded
<aDe> eww
> the moment python loads numpy 
> even if numpy .so *had* a RPATH
> the python loader has no DT_RPATH parsing code
* db_ ponders
> going around and setting RPATH in every module python uses if fortran is
+used is a pita
> and will not presently work anyway for the reasons I outlined above

<aDe:#bsdports> well .. the python loader could theoretically be taught to
+understand DT_RPATH
*** You are now talking to channel #bsdports
> aDe: yes
> but rtld is preloaded by the kernel and does the actual symbol resolving
> so if a DT_RPATH is present, the python loader is still going to have to
+punt to the rtld and tell it something is up
> and that means *every* single python load module needs to be checked for a
+fortran lib
> so I need to debug more ;)
<aDe> or get fortran support for clang? ;)
> That would be nicer
> but still leaves us probems with mixed modules
> if someone wants to try gcc instead of clang f'r instance
<aDe> sure .. that's the core problem

<xmj> db_: 18:57:51 <@xmj> 184775 (old) 188114 188327


fblas.so from scipy

        d_tag: DT_RPATH
        d_val: /usr/local/lib/gcc47

entry: 8
        d_tag: DT_INIT
        d_ptr: 0x7f58

entry: 9
        d_tag: DT_FINI
        d_ptr: 0x241f8

entry: 10
        d_tag: DT_HASH
        d_ptr: 0x158

entry: 11
        d_tag: DT_STRTAB

zsh: done       elfdump -a /usr/local/lib/python2.7/site-packages/scipy/lib/blas/fblas.so | 
zsh: suspended  more
night% elfdump -a /usr/local/lib/python2.7/site-packages/scipy/lib/blas/fblas.so

cc: numpy/random/mtrand/mtrand.c
cc -shared -Wl,-rpath=/usr/local/lib/gcc47 -L/usr/local/lib/gcc47 -B/usr/local/bin -O2 -pipe -fno-strict-aliasing build/temp.freebsd-9.1-STABLE-amd64-2.7/numpy/random/mtrand/mtrand.o build/temp.freebsd-9.1-STABLE-amd64-2.7/numpy/random/mtrand/randomkit.o build/temp.freebsd-9.1-STABLE-amd64-2.7/numpy/random/mtrand/initarray.o build/temp.freebsd-9.1-STABLE-amd64-2.7/numpy/random/mtrand/distributions.o -Lbuild/temp.freebsd-9.1-STABLE-amd64-2.7 -o build/lib.freebsd-9.1-STABLE-amd64-2.7/numpy/random/mtrand.so

% ldd -a /usr/local/lib/python2.7/site-packages/numpy/random/mtrand.so    
/usr/local/lib/python2.7/site-packages/numpy/random/mtrand.so:
        libc.so.7 => /lib/libc.so.7 (0x80081b000)

 ldd -a /usr/local/lib/python2.7/site-packages//numpy/core/_dummy.so|more
/usr/local/lib/python2.7/site-packages//numpy/core/_dummy.so:
        libm.so.5 => /lib/libm.so.5 (0x801601000)
        libc.so.7 => /lib/libc.so.7 (0x80081f000)
/lib/libm.so.5:
        libc.so.7 => /lib/libc.so.7 (0x80081f000)


<xmj> db_: or never?
>  ldd -a /usr/local/lib/python2.7/site-packages/numpy/random/mtrand.so    
>  /usr/local/lib/python2.7/site-packages/numpy/random/mtrand.so:
>         libc.so.7 => /lib/libc.so.7 (0x80081b000)
> ho ho ho!
> The linker see's no reference to a gcc lib so it ignores the rpath
> later on when python loads numpy it fails to see an rpath as well


DLOPEN(3)              FreeBSD Library Functions Manual              DLOPEN(3)

NAME
     dlopen, fdlopen, dlsym, dlfunc, dlerror, dlclose -- programmatic inter-
     face to the dynamic linker

LIBRARY
     Standard C Library (libc, -lc)

DESCRIPTION
     These functions provide a simple programmatic interface to the services
     of the dynamic linker.  Operations are provided to add new shared objects
     to a program's address space, to obtain the address bindings of symbols
     defined by such objects, and to remove such objects when their use is no
     longer required.


void *
dlopen(const char *name, int mode)
{

        return (rtld_dlopen(name, -1, mode));
}

This works...
export LD_PRELOAD=/usr/local/lib/gcc47/libgfortran.so



% more hello.c
#include <stdio.h>

int
main(void)
{
        printf("Hello world!\n");
}
% 

cc -c hello.c

cc -Wl,-rpath=/usr/local/lib/gcc47/libgfortran.so -o hello hello.o

elfdump -a hello |more
...
entry: 1
        d_tag: DT_RPATH
        d_val: /usr/local/lib/gcc47/libgfortran.so
...