From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1498) id 323DB385840A; Fri, 5 Nov 2021 21:08:49 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 323DB385840A MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Sandra Loosemore To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-4959] Fortran: Add more documentation for mixed-language programming [PR35276] X-Act-Checkin: gcc X-Git-Author: Sandra Loosemore X-Git-Refname: refs/heads/master X-Git-Oldrev: 8f4860f956871c3fd77ed60567d707490104f370 X-Git-Newrev: 452a0afbace650d7c0f2811e2b47e62dcd18e1fd Message-Id: <20211105210849.323DB385840A@sourceware.org> Date: Fri, 5 Nov 2021 21:08:49 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Nov 2021 21:08:49 -0000 https://gcc.gnu.org/g:452a0afbace650d7c0f2811e2b47e62dcd18e1fd commit r12-4959-g452a0afbace650d7c0f2811e2b47e62dcd18e1fd Author: Sandra Loosemore Date: Fri Nov 5 14:01:03 2021 -0700 Fortran: Add more documentation for mixed-language programming [PR35276] 2021-11-05 Sandra Loosemore PR fortran/35276 gcc/fortran/ * gfortran.texi (Mixed-Language Programming): Talk about C++, and how to link. Diff: --- gcc/fortran/gfortran.texi | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/gcc/fortran/gfortran.texi b/gcc/fortran/gfortran.texi index f3a961e4c1b..326470964b0 100644 --- a/gcc/fortran/gfortran.texi +++ b/gcc/fortran/gfortran.texi @@ -2718,11 +2718,23 @@ reading from the position marked previously. * Naming and argument-passing conventions:: @end menu -This chapter is about mixed-language interoperability, but also applies -if one links Fortran code compiled by different compilers. In most cases, -use of the C Binding features of the Fortran 2003 standard is sufficient, -and their use is highly recommended. - +This chapter is about mixed-language interoperability, but also +applies if you link Fortran code compiled by different compilers. In +most cases, use of the C Binding features of the Fortran 2003 and +later standards is sufficient. + +For example, it is possible to mix Fortran code with C++ code as well +as C, if you declare the interface functions as @code{extern "C"} on +the C++ side and @code{BIND(C)} on the Fortran side, and follow the +rules for interoperability with C. Note that you cannot manipulate +C++ class objects in Fortran or vice versa except as opaque pointers. + +You can use the @command{gfortran} command to link both Fortran and +non-Fortran code into the same program, or you can use @command{gcc} +or @command{g++} if you also add an explicit @option{-lgfortran} option +to link with the Fortran library. If your main program is written in +C or some other language instead of Fortran, see +@ref{Non-Fortran Main Program}, below. @node Interoperability with C @section Interoperability with C