https://bugzilla.redhat.com/show_bug.cgi?id=1129443
--- Comment #6 from Petr Pisar ppisar@redhat.com --- spamassissin uses ExtUtils::MakeMaker from sa-compile.raw like this:
my $ccopt = $Config{optimize}; # typically "-O2"
open(FILE, ">Makefile.PL") or die "cannot create Makefile.PL: $!"; print FILE <<"EOT" or die "error writing to Makefile.PL: $!"; use ExtUtils::MakeMaker;
WriteMakefile( 'NAME' => '$modname', 'VERSION_FROM' => '$PMFILE', 'ABSTRACT_FROM' => '$PMFILE', 'OBJECT' => '$(O_FILES)', 'OPTIMIZE' => '$ccopt', 'AUTHOR' => 'A. U. Tomated <automated@example.com>', ); EOT
See the OPTIMIZE (and following not quoted XS code)---it fiddles with CFLAGS. Therefore spassassin is the case why perl-ExtUtils-MakeMaker needs perl-devel.
This is classic counterexample for your complain "We don't need perl-devel".