Windows support through Opam 2.2

[AllanBlanchard]

FYI, we worked a little bit on porting Frama-C to Windows in Opam 2.2. We had to fix zlib and gmp which are also necessary for Alt-Ergo but we could not really figure out how to fix Alt-Ergo.

The fixes that we prepared are available here: ocaml/opam-repository@master...zilbuz:opam-repository:frama-c-windows

In Alt-Ergo, I slightly modified /src/bin/text/dune, adding a condition enabled_if for the flags, and for now just adding a rule for Windows that uses the standard flags, however, if I can build the executable, it just fails to run currently, so I guess that diving in the code of Alt-Ergo might be necessary.

[bclement-ocp]

Thanks for the report & extra information.
For tracking purposes: assigning @Halbaroth since this is essentially a duplicate of #919

[Halbaroth]

Good news, Alt-Ergo works on Windows through Opam 2.2 now! We support installations with both MSYS2 and Cygwin.
You can try to setup it with:

opam pin https://github.com/OCamlPro/alt-ergo.git#next 

Please, let me know if you have an issue.

Your patches have been helpful but when I tried it, I need to patch camlzip too and it seems I did something wrong because Alt-Ergo crashed frequently, depending on the environment in which we loaded it. I believed it was a problem related with the linked libraries but after some of patches of Basile Desloges have been pushed on opam-repository, everything works fine.

Alt-Ergo will officially support Windows in the next release 2.6.0, which should be published in September.

Notice that some features are not available on Windows (see #1201). We plan to support timelimit and :reproduce-resource-limit in 2.7.0. Tell me if you need it in the next release.

[AllanBlanchard]

Sorry for this long silence, I was in vacation ^^.

I installed the package this morning and got the following warning:

[WARNING] C:\Users\ab238114\AppData\Local\opam\default\bin\alt-ergo.exe is a Cygwin-linked executable

And when I try to run the exectuable, nothing happens but the return value is false:

PS C:\> alt-ergo.exe --version
PS C:\> echo $?
False

Notice that some features are not available on Windows (see #1201). We plan to support timelimit and :reproduce-resource-limit in 2.7.0. Tell me if you need it in the next release.

I guess that it means that Why3 will not be able to stop alt-ergo, but since Why3 still cannot compilable on Windows via Opam 2.2, I guess that it is not that problematic for us :P . From a business perspective it is not a problem for now: we have workaround for the very few people working on Windows and most of them do not use WP (thus, they do not use Alt-Ergo). It might be a "problem" for me for teaching in march 2025 if:

• we succeed in creating a Windows package for Frama-C before that,
• why3 works on Windows at this point,
• Alt-Ergo 2.7.0 is not released at this point.

[Halbaroth]

Sorry for this long silence, I was in vacation ^^.

I installed the package this morning and got the following warning:

[WARNING] C:\Users\ab238114\AppData\Local\opam\default\bin\alt-ergo.exe is a Cygwin-linked executable

And when I try to run the exectuable, nothing happens but the return value is false:

PS C:\> alt-ergo.exe --version
PS C:\> echo $?
False

Notice that some features are not available on Windows (see #1201). We plan to support timelimit and :reproduce-resource-limit in 2.7.0. Tell me if you need it in the next release.

Thanks for the bug report. I will investigate. I need bit of information:

1. Did you try to install Alt-Ergo with a fresh opam setup?
2. Did you install Cygwin by yourself and you use the opam init script to setup Cygwin?
3. Did you try to run Alt-Ergo in bash through Cygwin?

I guess that it means that Why3 will not be able to stop alt-ergo, but since Why3 still cannot compilable on Windows via Opam 2.2, I guess that it is not that problematic for us :P .

I didn't check but I guess that Why3 can kill a subprocess if it exceed the time limit. We plan to support timelimit on Windows through GC alarms.

From a business perspective it is not a problem for now: we have workaround for the very few people working on Windows and most of them do not use WP (thus, they do not use Alt-Ergo). It might be a "problem" for me for teaching in march 2025 if:

* we succeed in creating a Windows package for Frama-C before that,

* why3 works on Windows at this point,

* Alt-Ergo 2.7.0 is not released at this point.

We can publish a small release if you really need this feature before the 2.7.0.