[petsc-dev] Has anyone seen this? mpich flat_namespace results in segfaults

[Brad Aagaard]

The debugger shows the segfault ends up at
misaligned_stack_error_entering_dyld_stub_binder()

Here is the discussion of this issue on the libmesh-devel mailing list:
http://www.mail-archive.com/libmesh-devel@lists.sourceforge.net/msg04078.html

The only time I get this segfaulting in building/testing PyLith is 
within netcdf routines. This same error occurs in the nctest for both 
4.1.3 and 4.2.1. Building netcdf with the same gcc compilers works fine, 
but when I build netcdf with mpicc, I get this segfaults in the nctest. 
When I remove the flat_namespace link flag from mpicc, mpicxx, etc, 
these segfaults are gone. This started happening when I moved from a 
laptop running OSX 10.6 to a laptop running 10.8.

Brad

On 4/12/13 11:08 AM, Matthew Knepley wrote:
>  From Brad:
>
> * mpich linking flags are broken/fragile for Lion and Mountain Lion
>
>    mpich wants to add -flat_namespace to the linking flags. I think this
> is based on --enable-shared-libs=osx-gcc. The flat_namespace doesn't
> work in many cases on Lion and Mountain Lion-- it caused dynamic library
> loading to fail for netcdf, resulting in odd segmentation faults. It
> took me a long time to figure this one out. I finally found an email
> chain in the libmesh mailing list discussing this problem. I am not
> quite sure how PETSc handles building mpich on Lion and Mountain Lion.
> It may be extremely fragile in that other things built with the mpich
> compilers may segfault when loading dynamic libraries.
>
>    I fixed this by simply removing the flat_namespace flag from the
> mpicc, mpicxx, mpif90, mpif77 scripts after installing mpich but before
> using it.
>
>      Matt
>
> --
> What most experimenters take for granted before they begin their
> experiments is infinitely more interesting than any results to which
> their experiments lead.
> -- Norbert Wiener