Integrate changes #9584,9587 from maintperl into mainline.

Integrate changes #9584,9587 from maintperl into mainline.

keep eval"" CVs alive until the end of the statement in which
they're called

add README.macos (from Chris Nandor)

tyop in change#9555

p4raw-link: @9587 on //depot/maint-5.6/perl: d72c2fc956b5cb46ede17d06f89a463c78f1cf5f
p4raw-link: @9584 on //depot/maint-5.6/perl: e6fbcc36a54a8afd8dbcdcb9a8d8e178df530b97
p4raw-link: @9555 on //depot/perl: 6a0af2f17bcde4767b90a72eff7083c5effff21d

p4raw-id: //depot/perl@9588
p4raw-branched: from //depot/maint-5.6/perl@9583 'branch in'
	README.macos
p4raw-integrated: from //depot/maint-5.6/perl@9583 'copy in'
	pod/perlfaq9.pod (@9585..) 'merge in' scope.h (@8568..)
	pod/perl.pod (@8986..) MANIFEST (@9227..) win32/Makefile
	(@9286..) pp_ctl.c scope.c (@9288..) global.sym (@9289..)
	embed.h embed.pl objXSUB.h perlapi.c proto.h (@9292..)
	pod/buildtoc.PL (@9312..) win32/makefile.mk (@9495..) sv.c
	(@9496..) pod/perlguts.pod (@9514..)