Yosys error: can't guess frontend for input file

Hi, I just started with the Alchitry Cu and Alchitry labs 2.0.9 on Windows 11. When I try to build a simple project to drive the LEDs with some buttons, I get the following error from yosys and it exits with status 1. I get there by setting the toolchain to Yosys and clicking the build button.

ERROR: Can’t guess frontend for input file `Learning\gsw_fpgas\chapter2\switches_to_leds\build\alchitry.json -top MI_alchitryTop’ (missing -f option)!

Does anyone know how to troubleshoot or fix this issue? Thanks!

This sounds like a bug. I opened an issue for it here Yosys error: can’t guess frontend for input file · Issue #8 · alchitry/Alchitry-Labs-V2 · GitHub

I’ll be working on Alchitry Labs tomorrow and I’ll look into this.

This issue shows up if you have a space in your project’s path or name. I’m looking into a fix.

Edit: Found a fix so it’ll be fixed in 1.0.10.

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Removing the space from the file path did indeed allow Yosys to run, but now I am running into a new error in the build process. Any ideas?

I ran into this error once and reinstalling Alchitry Labs fixed it for me. Not 100% sure what caused it.

I also have the error shown where the program yosys-abc cannot be run. (“Access denied” and then “Yosys exited with status: 1”.) I tried with 2.0.22-BETA downloaded both directly from Alchitry and then via the Windows store. I tried with 2.0.23-BETA downloaded from Alchitry. I tried reinstalling per the suggestion from July.

To further debug, I opened a Windows command window and navigated to the directory shown in the logs to contain yosys-abc. (One can only access that directory in an elevated session as Adminstrator, so everything that follows was done with privilege.) The executable yosys-abs.exe does exist in that directory, but I could not run it from the command line either. I could copy the contents of that directory into a directory on my user path. From that copied location, I can run yosys-abs with the arguments shown in the log and process the file that the IDE was attempting to process when it died.

The upshot seems to be that the program cannot run in the restricted directory under WindowsApps, even with Administrator privileges. I don’t see anyway to install the IDE differently. As such, I don’t see a work around other than to try to run the remaining steps manually and outside the IDE.

Is there something I missed, or is this a bug that could be addressed?

(Added: This is on Windows 10 Pro with all current updates.)

From the GitHub releases page you can download the Windows files.

I’ll try and dive into this more later today but it might be tomorrow.

The last two days I’ve been down the rabbit hole with this issue. It turns out I “fixed” it before when trying to diagnose it and giving myself access to the WindowsApps folder (probably not a good idea on a computer you normally use).

I can confirm I can reproduce it consistently on fresh installs and that not using the files directly instead of the installer works fine.

I’ll post if/when I figure out a real solution.

I finally figured it out.

I should have a new build out tomorrow with it fixed.

This is fixed in 2.0.24-BETA. Thanks.