make re-exec regression in 'make -sf -' mode

[Sergei Trofimovich]

Noticed the regression on lowdown-0.10.0 upstream package.

Here is a complete trigger:

    $ printf 'all:\n\techo $(CC)' | make -sf -

[good] GNU make 4.3 works as expected:

    $ printf 'all:\n\techo $(CC)' | make -sf -
    cc

[bad] GNU make from git loops indefinitely in re-execution:

    $ printf 'all:\n\techo $(CC)' | ./make -sf -
    <hung>

Curiously space separation workaround is enough to
get the result:

    $ printf 'all:\n\techo $(CC)' | ./make -s -f -
    cc

Bitsect points at commit 7c4e6b0299 "[SV 60595] Restart
whenever any makefile is rebuilt".

-- 

  Sergei