I've tried many times to build KDE5 on a *new* KDE Linux Mint 18.2 install from source using these instructions:
https://community.kde.org/Guidelines_an ... rom_source

They don't work. Not even close. The prerequisites aren't all listed. After I've installed every qt5 development package it's possible to install on Mint, it now wants qt5.7 development files. That's probably not going to do it either. It seems like the developers are only testing out their build script on machines which are already development machines. It's probably not possible to see what the actual list of dependencies is.

Does anyone have instructions they think will work? I'm willing to field test them and post the results if you do.

The instruction there should definitely work and they have been tested. That said, that version of Mint has Qt 5.6.1 according distrowatch. Qt 5.6.1 is not enough for many programs (definitely not for Plasma master, and also for the latest version of Frameworks).

Which error messages do you get exactly, and what are you trying to compile?

I'm following the guideline and trying to build using the recommended command:
kdesrc-build --include-dependencies grantlee libkomparediff2 kdevplatform kdevelop-pg-qt kdevelop

I get a long series of things not being found. To fix errors, so far I installed the following:
libkf5geomap extra-cmake-modules libkf5-coreaddons-dev libkf5-coreaddons-bin-dev libkf5config-bin-dev libkf5codes-dev libkf5config-dev kf5xmlgui-dev kf5I18n-dev kf5KIO-dev qtquick1_5-dev qtdeclarative5-dev kf5doctools qtdeclarative-kf5declarative plasma_workspace-dev ................. and a few others I didn't take good enough notes to report.

Right now 6 packages build successfully (including grantlee) and a long list doesn't build, including kdevelop. In the kdevelop error.log, it carps that it wants Qt 5.7.0 but I only have Qt 5.6.1. I'm sure that's a problem. There isn't an update available on Mint repositories. I might be able to make it myself, but I thought that this was getting to be a little much.

I've been banging on this for a while now and the unmet dependencies don't seem to end. I'm really sure there's a missing magic step. I'm not sure why I had to manually add all those dependencies. I ran the apt-get statement provided and also manually added cmake and autotools before that. Any help is appreciated.

If you use --include-dependencies, all the KF5 packages are compiled as well, so you don't need to install them. You may need to install all Qt -dev packages, and the other dependencies required by each other component. There is no magic list because the names of the packages depend on the distribution used.

Even with the dependencies installed, they may be the wrong versions; and see my previous message, Qt 5.6.x is not enough for most of the components.

If you just need to install kdevelop, then don't use --include-dependencies and only compile those modules ( grantlee libkomparediff2 kdevplatform kdevelop-pg-qt kdevelop); you should be able to use the dependencies provided by your distribution (KDevelop developers are keeping not-so-last-minute dependencies for kdevelop components).

In alternative to the above points:
- use the appimage standalone version from the kdevelop website;
- use a distribution which provides more updated component

I'll try contacting the authors of kdesrc-build. In the mean time, the most popular linux distro (Mint) can't do an automated build of most of KDE because of dependency issues. I'm sure it's an easy fix. I was kind of hoping someone on these forums would know what it is. Maybe switch distros?

I already wrote that changing distribution is a possible solution.

Another one is compile also Qt, separately from the system one, and use that one to compile the rest of the packages.

That said, I'm not sure that "most popular linux distribution" really apply to Mint.

I have switched distros to Fedora 26. I have built and installed Qt 5.9.2. Almost everything builds now. However, cmake isn't finding my Qt 5.9 installed in /usr/local/Qt-5.9.2. Instead, it see the Qt 5.7 installed by the package manager. Since 5.9 is required by the current KDE5, it wont' build.

Do you have any suggestions how to make cmake aware of the local install of 5.9? I've tried manually setting the qtdir in .kdesrc-buildrc to the root directory of the local install (listed above). It ignores it. Should I be setting it somewhere else? I seem to remember there is a Qt script somewhere that build packages call to set their Qt variables. I can't remember what it is, but if it calls the one installed by the package manager, it's going to get the 5.7 Qt locations. However, I can't just change this script because I'm not sure how the whole system would behave with the upgrade.

Any further suggestions? Do you think I should move this to a different forum?

I should also mention that kdesrc-build is not finding the poppler & epub optional libraries, which were installed via package manager. I could use some help in general on giving the build script some help finding things.