T11545 fails with panic!
Ubuntu 18.04, master 6e8e2e08, booted with GHC-8.10.4
./hadrian/build --jobs=16 --build-root=_build_master --flavour=quick test --only=T11545
=====> 1 of 1 [0, 0, 0]
Compile failed (exit code 1) errors were:
ghc: panic! (the 'impossible' happened)
(GHC version 9.1.20210408:
heap overflow