# Ann: SWI-Prolog 10.1.5 **URL:** \ **Category:** Releases\ **Created:** [March 11, 2026, 4:39pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541 "2026-03-11T16:39:18Z")\ **Posts on this page:** 8\ **Page:** 2
**Author:** ![jan](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/jan/32/4_2.png) [@jan](https://swi-prolog.discourse.group/u/jan)\ **Post date:** [March 15, 2026, 1:36pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/21 "2026-03-15T13:36:00Z")
> [@alanbur](#): > > FYI, I checked previous release builds, the last one that worked for me was 10.1.3. Can happen. In recent times a lot of work has been done on portability and (C) standard compliance. That introduces portability issues as well ☹ Before release, building is tested on Fedora (latest), Windows (cross compiling using MinGW in a Fedora Docker image), MacOS (latest, both using Apple Clang and GCC), Debian bookworm (for Docker base image, no GUI), Ubuntu (PPA builds) and WASM. On Fedora some variants are tested, notably building without GMP and for single threading only. That is still only a tiny set from the many platforms and variations you can build. Notably SDL3 is not well settled and not yet widely available in stable distributions. The alternative was to develop for SDL2. That seemed a bad idea, even worse because SDL2 lacks some features that allows merging event dispatching and reading from `stdin`. ---
**Author:** ![rajeshkommu](https://avatars.discourse-cdn.com/v4/letter/r/a9adbd/32.png) [@rajeshkommu](https://swi-prolog.discourse.group/u/rajeshkommu)\ **Post date:** [March 15, 2026, 2:48pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/22 "2026-03-15T14:48:42Z")
I am able to build with PGO enabled now. Thanks for all your help ---
**Author:** ![alanbur](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/alanbur/32/7166_2.png) [@alanbur](https://swi-prolog.discourse.group/u/alanbur)\ **Post date:** [March 15, 2026, 8:42pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/23 "2026-03-15T20:42:20Z")
Another problem, unfortunately - the debugger doesn’t seem to work any more. Specifically, spy & gspy don’t work. ---
**Author:** ![jan](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/jan/32/4_2.png) [@jan](https://swi-prolog.discourse.group/u/jan)\ **Post date:** [March 16, 2026, 5:15pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/24 "2026-03-16T17:15:33Z")
> [@alanbur](#): > > Specifically, spy & gspy don’t work. Works fine for me. What exactly are you doing? ---
**Author:** ![alanbur](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/alanbur/32/7166_2.png) [@alanbur](https://swi-prolog.discourse.group/u/alanbur)\ **Post date:** [March 16, 2026, 6:23pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/25 "2026-03-16T18:23:16Z")
I’m using spy / gspy at the top level before calling the main for my app. The spypoint is never taken, unlike 10.1.3 where it is. As far as I can tell the spypoint just isn’t being set in 10.1.5, but I’m not sure how to confirm that. ---
**Author:** ![jan](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/jan/32/4_2.png) [@jan](https://swi-prolog.discourse.group/u/jan)\ **Post date:** [March 16, 2026, 6:37pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/26 "2026-03-16T18:37:38Z")
Ah, it seems there is an issue that spy/1 no longer enables debug mode :(. So, in addition you need to call ``` ?- debug. ``` The prompt should be tagged with `[debug]`. I’ll have a look. I’m traveling, so no guarantees. ---
**Author:** ![jan](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/jan/32/4_2.png) [@jan](https://swi-prolog.discourse.group/u/jan)\ **Post date:** [March 16, 2026, 6:41pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/27 "2026-03-16T18:41:16Z")
> [@jan](#): > > ’ll have a look Ok, that was easy. Pushed a fix. ---
**Author:** ![alanbur](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/alanbur/32/7166_2.png) [@alanbur](https://swi-prolog.discourse.group/u/alanbur)\ **Post date:** [March 16, 2026, 7:09pm UTC](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541/28 "2026-03-16T19:09:09Z")
> [@jan](#): > > Ok, that was easy. Pushed a fix. Yes, that’s done the trick 👍 Thank you very much 🙂 [Previous page](https://swi-prolog.discourse.group/t/ann-swi-prolog-10-1-5/9541.md?page=1)