2019-11-06 Jerry DeLisle <jvdelisle@gcc.ngu.org>
PR fortran/90374
* io.c (check_format): Allow zero width for D, E, EN, and ES
specifiers as default and when -std=F2018 is given. Retain
existing errors when using the -fdec family of flags.
* libgfortran/io/format.c (parse_format_list): Relax format checking for
zero width as default and when -std=f2018.
io/format.h (format_token): Move definition to io.h.
io/io.h (format_token): Add definition here to allow access to
this definition at higher levels. Rename the declaration of
write_real_g0 to write_real_w0 and add a new format_token
argument, allowing higher level functions to pass in the
token for handling of g0 vs the other zero width specifiers.
io/transfer.c (formatted_transfer_scalar_write): Add checks for
zero width and call write_real_w0 to handle it.
io/write.c (write_real_g0): Remove.
(write_real_w0): Add new, same as previous write_real_g0 except
check format token to handle the g0 case.
* gfortran.dg/fmt_error_10.f: Modify for new constraints.
* gfortran.dg/fmt_error_7.f: Add dg-options "-std=f95".
* gfortran.dg/fmt_error_9.f: Modify for new constraints.
* gfortran.dg/fmt_zero_width.f90: New test.
From-SVN: r277905
67732fbced