To: J3                                                     J3/23-201
From: HPC & Tom Clune
Subject: F202Y Global binding name for non C-interoperable
Date: 2023-June-14

Introduction
============

A relatively common approach to provide run-time configurable behavior
is through the use of dynamic libraries (DL). The interfaces for DLs
provide a mechanism for an application to call a procedure from a
dynamic library using the name of the library and the name of a desired
procedure.

The main difficulty in using with Fortran is that the DL interfaces
require specifying the _global_ binding name in the DL, and these are
non-portable due to Fortran compiler name mangling.

Note: This is _not_ intended to provide a mechanism to call a
procedure compiled with one compiler via a program compiled with a
different compiler.

Proposal
============
We propose to extend Fortran to improve portability when using a DL by
allowing users to control the global binding name of a subprogram that are
not necessarily C-interoperable.  A possible syntax would be to exploit the
similar capability to control global binding names via BIND(C,<name>) by
introducing BIND(Fortran,<name>). Alternatively we could come up with a new
attribute for a subprogram interface to specify the global name.