This is a tracker for bugs where either eg. "MAKEOPTS=-j1" or sth like "MAKEOPTS=-jN -lM" isn't working as expected.
For the record: The tinderbox sets MAKEOPTS="-j1" NINJAFLAGS="-j1" EGO_BUILD_FLAGS="-p 1" GOMAXPROCS="1" GO19CONCURRENTCOMPILATION=0 RUSTFLAGS="-C codegen-units=1" RUST_TEST_THREADS=1 RUST_TEST_TASKS=1