I see from https://gcc.gnu.org/install/test.html that it's possible to run tests in parallel. I get the impression from gcc/Makefile that the check concerned has to be set up in the Makefile (in my build tree, configured with --target=x86_64-apple-darwin16 --enable-languages=c,c++,ada,fortran,objc,obj-c++ , I see both lang_checks and lang_checks_parallelized set empty). So, is it necessary for check-ada or check-acats to cope with being run in parallel (i.e., will they ever see GCC_RUNTEST_PARALLELIZE_DIR set?)
Also in https://gcc.gnu.org/install/test.html, under what circumstances would a test report ERROR (the testsuite detected an error) or WARNING (the testsuite detected a possible problem)? For example, if a particular test that should compile & run has a build error, is that a FAIL or an ERROR?