make -j clean all doesn't work every time
make -j 3 clean all sometimes fail.
This system has two cores, running FreeBSD 8.2 and autoconf-2.69, automake-1.12, libtool-2.4.2
These are the failures, in order of frequency. The first failure is the most common by far. In total, I seem to have a failure rate of about 60%.
$ make -j 3 clean all
CCLD src/test/test gcc: src/test/src_test_test-test_data.o: No such file or directory gcc: src/test/src_test_test-tinytest.o: No such file or directory
CCLD src/or/tor gcc: src/or/tor_main.o: No such file or directory
CCLD src/test/test gcc: src/test/src_test_test-test_data.o: No such file or directory
Related to #6524 (moved).