[Bug fortran/79933] gfortran no longer able to compile dolfyn benchmark

[tulipawn at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79933

--- Comment #3 from PeteVine <tulipawn at gmail dot com> ---
In gcc 8, -std=f2003 is required to overcome the issue but there's another
failure later on:

gfortran -c -O2 -std=f2003    solverinterface.f90
solverinterface.f90:108:9:

    real*4  fpar(16)  ! hint by Shibo
         1
Error: GNU Extension: Nonstandard type declaration REAL*4 at (1)
solverinterface.f90:153:7:

        fpar(1) = RTOL(VarSC)
       1
Error: Unclassifiable statement at (1)
solverinterface.f90:154:7:

        fpar(2) = ATOL(VarSC)
       1
Error: Unclassifiable statement at (1)
solverinterface.f90:156:7:

        fpar(1) = RTOL(ivar) ! relative tolerance, must be between (0, 1)
       1
Error: Unclassifiable statement at (1)
solverinterface.f90:157:7:

        fpar(2) = ATOL(ivar) ! absolute tolerance, must be positive
       1
Error: Unclassifiable statement at (1)
solverinterface.f90:176:1:

         NNZ,  Alu,Jlu,Ju,Jw         )
 1

Are there any gfortran switches that would enable compiling this code base as
is?