The T7995 test appears to fail when using a GHC compiled with the quick build flavour:

=====> T7995(optasm) 1 of 1 [0, 0, 0]
cd "simplCore/should_compile/T7995.run" && $MAKE -s --no-print-directory T7995  < 
Wrong exit code for T7995()(expected 0 , actual 2 )
Stdout ( T7995 ):
Makefile:189: recipe for target 'T7995' failed
Stderr ( T7995 ):
make[2]: *** [T7995] Error 1
*** unexpected failure for T7995(optasm)

Unexpected results from:
TEST="T7995"

SUMMARY for test run started at Thu Oct 24 13:58:57 2019 
0:00:00.394518 spent to go through
       1 total tests, which gave rise to
      10 test cases, of which
       6 were skipped

       0 had missing libraries
       0 expected passes
       0 expected failures

       0 caused framework failures
       0 caused framework warnings
       0 unexpected passes
       1 unexpected failures
       0 unexpected stat failures
       0 fragile tests

Unexpected failures:
   simplCore/should_compile/T7995.run  T7995 [bad exit code (2)] (optasm)

This did not used to happen, so I can only assume this is a regression.

T7995 is unusual in that it checks to see if a rewrite rule in a function in the GHC API fires, which means that the results of this test are subject to the optimization levels used when compiling GHC. In light of this, I'm surprised that this test hasn't failed before.