[petsc-dev] ARG_MAX and linking

[Jed Brown]

If it's a __declspec(dllexport) issue, it's probably just not being
handled correctly in petscsys.h.  Actually, it could be this junk which
much be obsolete because we don't use CMake to build PETSc and also
don't define petsc_EXPORTS.

include/petscsys.h-#if defined(petsc_EXPORTS)      /* CMake defines this when building the shared library */
include/petscsys.h:#  define PETSC_VISIBILITY_PUBLIC PETSC_DLLEXPORT
include/petscsys.h-#else  /* Win32 users need this to import symbols from petsc.dll */                                                                                                        
include/petscsys.h-#  define PETSC_VISIBILITY_PUBLIC PETSC_DLLIMPORT                                                                                                                          
include/petscsys.h-#endif                                                            

Pierre Jolivet <pierre.jolivet at enseeiht.fr> writes:

> I’m on master.
> Thanks, I think this is the way to go, though I’m now seeing a lot of undefined references, like there http://mingw-users.1079350.n2.nabble.com/imp-prefixes-when-linking-td7386007.html <http://mingw-users.1079350.n2.nabble.com/imp-prefixes-when-linking-td7386007.html>
>
>> On 6 Feb 2018, at 2:05 PM, Jed Brown <jed at jedbrown.org> wrote:
>> 
>> What branch are you on?  I wonder if this is exacerbated by Scott's
>> "absolute path".  You can configure --with-single-library=0 which will
>> link a separate libpetscsys, libpetscvec, etc.
>> 
>> There are Cygwin recipes in gmakefile that create argument files that
>> the linker reads as @args.  We could use $(file > args, $^) to write
>> them with arbitrarily long command lines.
>> 
>> Pierre Jolivet <pierre.jolivet at enseeiht.fr> writes:
>> 
>>> Hello,
>>> I’m trying to compile PETSc with msys2 and MS MPI.
>>> Everything works out almost flawlessly, except when linking. Indeed, you generate a nice line of 
>>> $ wc /tmp/cl
>>>    2  1234 69041 /tmp/cl
>>> 69041 characters, but 
>>> $ getconf.exe ARG_MAX
>>> 32000
>>> 
>>> Thus, sadly, the make fails with the following error
>>> /usr/bin/sh: /mingw64/bin/gcc: Argument list too long
>>> 
>>> Do you know of a work around? Anyway to link the full library as multiple smaller libraries (I think you did that for some version X.Y with X << 3, didn’t you?)?
>>> 
>>> Thanks,
>>> Pierre