New consistency checks in reading DXF files

The question I joined to ask was answered elsewhere before my attempt to ask it here was approved. But I stlll have some things to say about it.

I built (on Fedora) the latest (not supposed to be safe) version and it was badly broken (by a pull request approved on Sep 2 2026 if I’m reading things correctly) then fixed by one today (Sep 14), none of which I would know if I hadn’t debugged it myself as a result of happening upon a bad moment to first grab the source code.

The DXF file format has a vast amount of redundant and/or useless content. (So far as I understand) LibreCAD previously read what it cared about and ignored what was redundant or useless or not handled. In that change on Sep 2, LOTS of checks were added to make sure lots of redundant and/or useless information was internally self consistent. If it isn’t consistent then reading the DXF file fails with no explanation: just failure, leading the user to believe the file itself was somehow inaccessible, rather than failed an unimportant consistency check.

So far all that is just a mis-feature, not a bug. It becomes a bug because files written by LibreCAD (in the currently stable versions) fails one of he consistency check. Today the pull request was approved to skip that one check.

It would make far more sense to tell the user more about what went wrong and/or make these checks a warning or configurable. Little purpose is served by being needlessly strict.

I’m currently on:

Version: 2.2.2_alpha1-659-g0b2d9b2f3
Compiler: GNU GCC 16.2.1
Compiled on: Sep 14 2026
Qt Version: 6.11.2
Boost Version: 1.90.0
System: Fedora Linux 44 (KDE Plasma Desktop Edition)

That includes skipping that one check, so files from released LibreCAD can be used.

The UI is far more changed from 2.2.1.2 (The Fedora build I’m also using) than one might expect. Some of that is much better. Some of it is incomprehensible so far, but might be good or still terrible after I understand it.

I started down this path hoping to fix (at least for myself) some of the UI misfeatures and bugs. The build from newer code has already fixed some of the bugs/misfeatures I would have fixed and changed to the point that some others are no longer relevant. It makes enough other things worse to be a questionable step forward, but I think those big changes do make this the right place for me to start (rather than starting from a stable version).

please report found issues to Issues · LibreCAD/LibreCAD · GitHub

The bug was apparently found and fixed by the original author of the bug at the same time I was trying to diagnose it. Before diagnosing it, I assumed it was my error in building the software, rather than a bug.

The topic of this thread is not really that bug. I was hoping for other comments on the philosophy of aggressive checking of redundant info in files. I’m not sure that is really an “issue” at this point rather than just a new feature that my long experience as a software engineer tells me was a poorly decided feature.