# Failed building SWI-Prolog from source **URL:** \ **Category:** General\ **Created:** [October 28, 2020, 1:05pm UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107 "2020-10-28T13:05:15Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![notooth](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@notooth](https://swi-prolog.discourse.group/u/notooth)\ **Post date:** [October 28, 2020, 1:05pm UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/1 "2020-10-28T13:05:15Z")
Hello, I failed building SWI-Prolog from source with this error. Can anyone help? > $ ninja > ninja: error: ‘…/man/ssl’, needed by ‘man/lib/prologpack.tex’, missing and no known rule to make it ---
**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:** [October 28, 2020, 1:20pm UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/2 "2020-10-28T13:20:29Z")
You probably didn’t install the `libssl-dev` dependency. See [https://www.swi-prolog.org/build/Debian.txt](https://www.swi-prolog.org/build/Debian.txt) for a full list of dependencies. Partial builds (leaving out some components) is not well supported for many combinations of extensions. Typically, just build the whole lot (least trouble) or just the core system if you want a minimal system, typically to be embedded in a service. ---
**Author:** ![notooth](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@notooth](https://swi-prolog.discourse.group/u/notooth)\ **Post date:** [October 28, 2020, 1:55pm UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/3 "2020-10-28T13:55:48Z")
I got it. Thanks. ---
**Author:** ![maximilianocristia](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/maximilianocristia/32/5377_2.png) [@maximilianocristia](https://swi-prolog.discourse.group/u/maximilianocristia)\ **Post date:** [January 11, 2025, 9:58pm UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/4 "2025-01-11T21:58:43Z")
Hello, I’m having the same problem here: ```prolog mcristia@maxi:~/tmp/swipl-devel/build$ ninja ninja: error: 'man/ssl', needed by 'man/lib/prologpack.tex', missing and no known rule to make it ``` Following Jan’s answer I tried installing libssl-dev (sorry for the Spanish): ```prolog mcristia@maxi:~/tmp/swipl-devel/build$ sudo apt-get install libssl-dev Leyendo lista de paquetes... Hecho Creando árbol de dependencias... Hecho Leyendo la información de estado... Hecho libssl-dev ya está en su versión más reciente (3.0.13-0ubuntu3.4). 0 actualizados, 0 nuevos se instalarán, 0 para eliminar y 7 no actualizados. ``` but it was already installed. I tried also installing libssl-doc but I’m still getting the same error: ```prolog mcristia@maxi:~/tmp/swipl-devel/build$ ninja ninja: error: 'man/ssl', needed by 'man/lib/prologpack.tex', missing and no known rule to make it ``` Also looked at [Prerequisites for Debian based systems (Ubuntu, Mint, ...)](https://eu.swi-prolog.org/build/Debian.html) and installed everything mentioned there. ---
**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:** [January 12, 2025, 8:58am UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/5 "2025-01-12T08:58:25Z")
Try re-running `cmake .` in the build dir. That should complain about the missing ssl. Does it? If so, you need to check the Cmake log/error files to see why. AFAIK, this should all build nicely on a wide range of Linux distributions and Prolog versions. But, sometimes there are failures as a result of broken installations, unexpected environment variables, etc ☹ ---
**Author:** ![maximilianocristia](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/maximilianocristia/32/5377_2.png) [@maximilianocristia](https://swi-prolog.discourse.group/u/maximilianocristia)\ **Post date:** [January 12, 2025, 11:52am UTC](https://swi-prolog.discourse.group/t/failed-building-swi-prolog-from-source/3107/6 "2025-01-12T11:52:59Z")
It worked!!! Thanks a lot!!! So the sequence is: if ninja gives that error, install libssl-dev, rerun cmake and then ninja again.