performance: 0.640 device: 0.622 debug: 0.577 network: 0.558 files: 0.549 other: 0.526 socket: 0.524 permissions: 0.506 semantic: 0.473 PID: 0.440 graphic: 0.427 vnc: 0.314 boot: 0.287 KVM: 0.060 Parallel build doesn't work after "make clean" After running "make clean" qemu won't build with -j option. When I run "./configure && make clean" and then make -j5, following errors occur: GEN config-host.h GEN trace.h GEN qemu-options.def GEN qmp-commands.h GEN qapi-types.h GEN qapi-visit.h GEN tests/test-qapi-types.h GEN tests/test-qapi-visit.h GEN tests/test-qmp-commands.h GEN qapi-generated/qga-qapi-types.h GEN qapi-generated/qga-qapi-visit.h GEN qapi-generated/qga-qmp-commands.h CC osdep.o CC qemu-thread-posix.o cc1: error: qapi-generated: No such file or directory [-Werror] cc1: all warnings being treated as errors make: *** [qemu-thread-posix.o] Error 1 make: *** Waiting for unfinished jobs.... cc1: error: qapi-generated: No such file or directory [-Werror] cc1: all warnings being treated as errors make: *** [osdep.o] Error 1 If you run "make -j5" once again after this, build continues succesfully because "qapi-generated" directory already exists. I think this should have been fixed at one point in time - at least it seems to work for me, so I'm closing this ticket now. If you still have problems, feel free to open this ticket again, but then please specify the exact version of QEMU which causes the trouble for you.