Re: gfortran 4.6 incompatible with previous?

[Tobias Burnus <burnus at net-b dot de>]

Sewell, Granville wrote:
> I know that gfortran 4.3 was not compatible with earlier versions (can't mix object code), but now a
> user is telling me that 4.6 is not compatible with 4.3, is that true?

The library .so version number of GCC 4.3 to 4.7 is the same and no 
symbol was deleted from libgfortran since 4.3 - though new symbols have 
been added such that a GCC 4.6 program might not work with a GCC 4.3 
libgfortran.

Thus, a newer libgfortran should work with older programs.

I am also not aware about any ABI issue. The only thing I am aware of 
are issues with REAL(16) and selected_real_kind. Namely, mixing a 
libgfortran on a system where libquadmath was available with one 
compiler which does not support libquadmath. That might to lead issues 
when a configure script tests for the available kind numbers in a 
certain way (such as HDF5 did).


Note: The gcc@gcc.gnu.org mailing list is about the development of GCC. 
Such questions are better suited for the gcc-help@gcc.gnu.org mailing 
list, though they might also be suited for the fortran@gcc.gnu.org.

Tobias