# Linux build instructions lead to using Qt 5.9.5 on Ubuntu 18.04

**URL:** <https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188>\
**Category:** Development\
**Tags:** build\
**Created:** [August 27, 2020, 9:38am UTC](https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188 "2020-08-27T09:38:43Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![cpinter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/cpinter/32/7995_2.png) [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Post date:** [August 27, 2020, 9:38am UTC](https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188/1 "2020-08-27T09:38:43Z")

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I followed the [build instructions for Linux](https://slicer.readthedocs.io/en/latest/developer_guide/build_instructions/linux.html#pre-requisites), and the prerequisites install command for Ubuntu apparently downloaded Qt 5.9.5, at least this is what the CMake configure output said.

The Ubuntu version mentioned in the instructions is 20.04, and what I use is the older 18.04.  
Is the old Qt version due to the older Ubuntu version? Is it verified that the instructions on 20.04 by default download 5.15.0?

Anyway I started installing Qt with the online installer. What I’d like to know is first if the instructions are correct for 20.04, and if yes, if there is a similarly easy way for 18.04?

Thank you!

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [October 4, 2020, 1:00pm UTC](https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188/2 "2020-10-04T13:00:37Z")

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I can confirm that the [20.04 instructions](https://slicer.readthedocs.io/en/latest/developer_guide/build_instructions/linux.html#ubuntu-20-04-focal-fossa) on the docs work.

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**Author:** ![Saima](https://avatars.discourse-cdn.com/v4/letter/s/9d8465/32.png) [@Saima](https://discourse.slicer.org/u/Saima)\
**Post date:** [April 14, 2021, 5:50am UTC](https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188/3 "2021-04-14T05:50:58Z")

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I got the errors below the build debug slicer failed. I followed instructions on [GNU/Linux Systems — 3D Slicer documentation](https://slicer.readthedocs.io/en/latest/developer_guide/build_instructions/linux.html#ubuntu-20-04-focal-fossa)

fstd/libsrc/CMakeFiles/ofstd.dir/build.make:62: recipe for target ‘ofstd/libsrc/CMakeFiles/ofstd.dir/ofchrenc.cc.o’ failed  
make[5]: \*\*\* [ofstd/libsrc/CMakeFiles/ofstd.dir/ofchrenc.cc.o] Error 1  
CMakeFiles/Makefile2:2304: recipe for target ‘ofstd/libsrc/CMakeFiles/ofstd.dir/all’ failed  
make[4]: \*\*\* [ofstd/libsrc/CMakeFiles/ofstd.dir/all] Error 2  
Makefile:140: recipe for target ‘all’ failed  
make[3]: \*\*\* [all] Error 2  
CMakeFiles/DCMTK.dir/build.make:113: recipe for target ‘DCMTK-prefix/src/DCMTK-stamp/DCMTK-build’ failed  
make[2]: \*\*\* [DCMTK-prefix/src/DCMTK-stamp/DCMTK-build] Error 2  
CMakeFiles/Makefile2:699: recipe for target ‘CMakeFiles/DCMTK.dir/all’ failed  
make[1]: \*\*\* [CMakeFiles/DCMTK.dir/all] Error 2  
Makefile:94: recipe for target ‘all’ failed  
make: \*\*\* [all] Error 2

can anyone help me fix the build on ubuntu 18.04.

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [April 18, 2021, 5:07am UTC](https://discourse.slicer.org/t/linux-build-instructions-lead-to-using-qt-5-9-5-on-ubuntu-18-04/13188/4 "2021-04-18T05:07:31Z")

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We don’t use Ubuntu 18.04 anymore, so we cannot provide specific build instructions, but if you figure out how to do it then please let us know and we will add it to the documentation.

About the specific error: you haven’t included the actual error message (just the status report that the build failed), so we don’t know what could have caused it. If you upload the complete build log somewhere and post the link here then we might be able to give advice.