Request for 32-bit Builds of openfast.exeand FAST.Farm.exefor OpenFAST v5

[linqing-009]

Dear：
I am currently running OpenFAST v5 on a 64-bit Windows system. My setup relies on a legacy 32-bit Bladed-format (DISCON) DLL controller.

As discussed in previous threads, a 64-bit OpenFAST executable cannot load a 32-bit DLL. Unfortunately, recompiling the controller DLL to 64-bit is not currently an option for my workflow.

A known workaround for this compatibility issue was implemented in OpenFAST v2.2.0 by providing 32-bit executables. Since the official GitHub Releases for OpenFAST v5 appear to contain only 64-bit builds, could the development team provide a 32-bit build of openfast.exeand FAST.Farm.exefor OpenFAST v5?

Thank you very much for your time and continued support!

[andrew-platt]

We currently don't supply any 32 bit compiled versions of OpenFAST. Intel began phasing out the ifortcompilers in favor of the newer IFX compilers starting in 2020. Along with phasing out ifort, they also removed support for 32 bit compilation. As we no longer have access to the older ifort compilers, we dropped support of 32 bit in the last year.

However, you do have two options to get OpenFAST working on 32 bits:

1. Install Visual Studio with an older ifort compiler suite and build.
2. Use an intermediate layer between the 64 bit OpenFAST and the 32 bit controller DLL. We developed a method to do this last year, but have not distributed it yet. There are currently two variants of this method: 1) loading an intermediate DLL that then loads the 32 bit controller DLL, and 2) a client-server architecture where a DLL is loaded that calls a local server running the 32 bit DLL. From the perspective of OpenFAST, both methods act as if it loaded the controller DLL directly.

I recommend trying out the second method as it will provide the most flexibility. @mayankchetan will post some details on where to find this and how to use it.

Regards,

[mayankchetan]

Hello @linqing-009,

you can find the repo @andrew-platt mentioned over here: https://github.com/mayankchetan/discon-wrapper

The README.md should provide you the instructions to setup, and any LLM like Codex or Claude Code might help you better in getting things up and running.

If you have any issues with it feel free to raise an issue on the discon-wrapper repo.

Regards,
Mayank

[andrew-platt]

Tagging this on 5.0.1 with the following action items:

• Add link to discon-wrapper to rtd (migrating this to the openfast org is a different discussion)
• Add brief discussion in FAQ section of rtd