Multiple Fortran compiler versions on a single machine

[GordonA]

At the moment we are bound to Visual Studio 2013, which in turn ties us to Intel Fortran 17.0 (Parallel Studio XE Composer). We are moving to Visual Studio 2019 in the New Year and via the oneAPI we have access to the more recent (and supported) compilers.

On a single machine is it possible to support code development in both environments, without having to re-install?
1. Visual Studio 2013/ifort 17  (legacy)
2. Visual Studio 2019/ifort 2021.2 Classic (current)

[JohnNichols]

Unless the real experts tell you otherwise it should work as oneapi will only install to 2017 and 2019 it will not see 2013.  And it installs in parallel to the old ifort, of course you could try it on a junk machine, everyone should have an old machine lying around.  

[GordonA]

Installing Fortran Classic 2021 seems to switch the compiler in VS2013 over to that version. Even though the VS plugin in 2013 still available for Parallel Studio 2017 (above).
I just wonder if it is possible to point VS2013 back to iFort 17?

[andrew_4619]

You can have more than one VS version loaded. When you install the Fortran compiler it will offer to integrate into any supported VS that it finds. The default is to integrate but you can chose which ones you want to integrate with.

[Steve_Lionel]

How to Select Intel® Fortran Compiler and Compiler Version in...

[Devorah_H_Intel]

Check system requirements as well, particularly OS supported. 

[GordonA]

Thanks for the replies. At the moment we need to support builds with VS2013 using a pre-oneAPI version of the iFort compiler.
What we are seeing is that when we install oneAPI the latest version is then also picked up by VS2013, as pervious screenshot (even though VS2013 is not supported by oneAPI - there is no option to "not select" 2013 as far as I can see). This means we lose our old VS2013 environment. 

Is it possible to point VS2013 back to iFort17?

[andrew_4619]

Interesting, it isn't meant to do that but clearly it is picking up the latest ifort from the environment somehow.  In VS 2013 do you have more than one version installed, if you change the default compiler from "latest" to a specific older older version does it respect that change? That might give some insight into a 'fix'.   It is clear that intel will not be fixing anything on this as it is all relating to out of support versions.

[GordonA]

Thanks - VS2013 is out of support I know,  but I am hoping that there might be an option somewhere, in VS2013 itself or a config file change, that would allow us to switch away from the "latest".

[andrew_4619]

I assume you looked at tools>options>intel compilers and libraries settings?