Fortran_Calls_C Mixed Language Readme

This example demonstrates calling a C subroutine from Fortran, using the C interoperability features first introduced in Fortran 2003.

The C subroutine is in a static library project Clib. This is made a "dependent" project of the Fortran main project Fmain, which will cause the library to be automatically linked in with the Fortran main program.

System Requirements:

Microsoft Visual Studio 2013*, 2015* or 2017* Professional Edition or above
Intel® Parallel Studio XE 2019 Composer Edition for Fortran Windows* or newer

Build Instructions:

For Visual Studio IDE users:

Open Visual Studio and load the solution .sln file
Clean the solution from menu Build > Clean Solution
Build the project from menu Build > Build Solution
Run the application from menu Debug > Start Without Debugging or press Ctrl-F5

For Command line users:

Open the Intel Visual Fortran Build Environment window from Start menu and navigate to the sample folder
Use following commands to build and test:
1. Clean the build folder use: build.bat clean
2. To build a release version: build.bat release
3. To build a debug version: build.bat debug
4. To run the program: build.bat run

Notes:

In all mixed-language programming, it is important that all the projects link to the same set of run-time libraries, static vs. dynamic, debug vs. release. Microsoft Visual C++ chooses different defaults for this than Intel Visual Fortran - here we have chosen to change the C project from dynamic libraries to static libraries, to match the Fortran.

Fortran_Calls_C Mixed Language Sample