check flags:    
[pbuilding check-recursive
Making check in lib
[pmake[1]: Entering directory `/tmp/nix-build-m6khl1rc8hzmkz5m9naqyh6phzlrw4bc-config-support.drv-0/config-support-1.4/lib'
make[1]: Nothing to be done for `check'.
make[1]: Leaving directory `/tmp/nix-build-m6khl1rc8hzmkz5m9naqyh6phzlrw4bc-config-support.drv-0/config-support-1.4/lib'
[q[pmake[1]: Entering directory `/tmp/nix-build-m6khl1rc8hzmkz5m9naqyh6phzlrw4bc-config-support.drv-0/config-support-1.4'
make[1]: Nothing to be done for `check-am'.
make[1]: Leaving directory `/tmp/nix-build-m6khl1rc8hzmkz5m9naqyh6phzlrw4bc-config-support.drv-0/config-support-1.4'
[q[q