Tcl 9 breaks build

[BsAtHome]

The new Tcl/Tk 9 release, included in Fedora 42 and 43, breaks the LCNC build. Python on the system is compiled using Tcl/Tk 9 and can therefore not be downgraded to 8.6 development packages. Additionally, it seems that the tclX package cannot be found as it is apparently an 8.6 version package, but this just be a symptom of "extension-package-no-longer-needed".

There are a lot of "kludges" in the sources handling many different versions older than 8.6 too. Since master no longer supports old Debians anyway, it would be prudent to clean up the sources and remove the old kludges. Both Bookworm and Trixie use 8.6, so dropping older versions should not be a problem for master. It can be expected that newer Debians will move to the tcl 9 too (Trixie already has a tcl9.0 deb), so this needs to be fixed sooner than later.

[rmu75]

Is it just a build-system issue or are there changes necessary to tcl/tk code also? Is anybody actively developing tcl/tk stuff?

[BsAtHome]

This is more than "just a build issue". A lot of tk api got deprecated and removed in the transition from tcl8 to tcl9.

It seems that most things can be handled relatively easily (it compiles), but I have not yet been able to test a working frontend. There were a lot of other small issues that needed to be handled (like me running python 3.14).

And for the development stuff... there are many utilities based on the tcl code and, f.ex., the axis frontend is a lot of tcl. There is no way around porting unless you want to deprecate and remove half the user-facing code.

[rene-dev]

a few UI components and hal helpers use tcl.

• twopass
• halshow
• halconfig
• config picker
• ngcgui
• tooltable editor
• halcheck
• check_config
• parts of axis

https://github.com/search?q=repo%3ALinuxCNC%2Flinuxcnc+language%3ATcl+&type=code

[andypugh]

Also bear in mind that HAL files can be Tcl.
eg: https://github.com/LinuxCNC/linuxcnc/blob/master/lib/hallib/plasmac.tcl
Though it is unlikely that these use anything that has changed

[andypugh]

I guess the main question is whether Tcl9 code will run on Tcl8. If not then we will have a bit of a headache.

[rmu75]

It doesn't look too bad https://core.tcl-lang.org/tcl/wiki?name=Migrating%20scripts%20to%20Tcl%209, https://core.tcl-lang.org/tcl/wiki?name=Migrating%20C%20extensions%20to%20Tcl%209

[hansu]

I volunteer to migrate halshow 😉

But is there a way to easily test that instead of setting up a new system with Fedora 42 or something that uses TCL 9?

[BsAtHome]

So far, the config picker is working and the splash-screen using the default axis sim shows. Then I get a segfault that I yet need to trace down.

There were so far very few changes required and only one incompatible change between tcl8 and tcl9 needed to be implemented. That will have to be sorted out once I get it all working. But I suppose it will be a build-time thing to adapt the sources according to the version.

[rmu75]

But is there a way to easily test that instead of setting up a new system with Fedora 42 or something that uses TCL 9?

you could "debootstrap" a fedora 42 system into a chroot, should be sufficient for this.

[BsAtHome]

If you do, you should use fedora 43, which is current.

[rene-dev]

There are debian and ubuntu packages for tcl9

[rmu75]

There are debian and ubuntu packages for tcl9

Proper testing needs python / tkinter built against tcl/tk 9.