a bug in kLineEdit causes spurious emission of textEdited signals when calling setText().
This in turn causes spurious calls of compilerEdited() when selecting a compiler in the compilers window,
which leads to a segfault (e.g. this bug https://bugs.kde.org/show_bug.cgi?id=373004) and I think some duplicates also.
I have submitted also a patch to kcompletion, https://phabricator.kde.org/D9808
This is a workaround for those systems until that is fixed