Created attachment 156175 [details] example project When building a build target that's in a subfolder, KDevelop calls ninja with the target name but ignores the folder, which ninja doesn't recognize as a valid build target, so the build fails.
Does this bug affect only Meson projects? Not CMake? If so, the component should be changed to "Build tools: Meson".
The bug only affects Meson. It seems there is a difference between how meson and cmake generates output for ninja. So if I for example generate two projects with a similar structure, say something like below for cmake: . ├── CMakeLists.txt ├── main.cpp └── subfolder ├── CMakeLists.txt └── test_stuff_cmake.cpp And for meson something like this: . ├── main.cpp ├── meson.build └── subfolder ├── meson.build └── test_stuff.cpp After building the respective projects, if I issue the command 'ninja -t targets all' I can see that the the CMake project will have in the output: subfolder/CMakeFiles/test_stuff_cmake.dir/test_stuff_cmake.cpp.o: CXX_COMPILER__test_stuff_cmake_unscanned_Debug subfolder/test_stuff_cmake: CXX_EXECUTABLE_LINKER__test_stuff_cmake_Debug test_stuff_cmake: phony Whereas the meson generated project does not have the last entry: subfolder/test_stuff.p/test_stuff.cpp.o: cpp_COMPILER subfolder/test_stuff: cpp_LINKER That means kdevelop will succeed on building the dependent cmake target > /usr/bin/ninja test_stuff_cmake but fail on a similar meson target: > /usr/bin/ninja test_stuff ninja: error: unknown target 'test_stuff' *** Failure: Exit code 1 *** Will result in the error that is reported here.