https://issues.dlang.org/show_bug.cgi?id=15224

          Issue ID: 15224
           Summary: making 'clean' results in garbage commands
           Product: D
           Version: D2
          Hardware: All
                OS: Mac OS X
            Status: NEW
          Severity: regression
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

and then it fails:
----
make -fposix.mak DMD=../dmd MODEL=32 clean
make -C test/init_fini clean
rm -rf ./generated///32
make -C test/exceptions clean
rm -rf ./generated///32
make -C test/coverage clean
Makefile:29: warning: overriding commands for target
`generated///32/no_code.done'
Makefile:14: warning: ignoring old commands for target
`generated///32/no_code.done'
rm -rf ./generated///32 *.lst
make[1]: *** No rule to make target `test/profile/.clean', needed by `clean'.
Stop.
make: *** [clean] Error 2
-----

what are those bogus filenames with /// in them?

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