[perl #114984] Glob.xs: Extend stack when returning

If a pattern passed to File::Glob consists of a space-separated list
of patterns, the stack will only be extended by doglob() enough for
the list returned by each subpattern.  So iterate() needs to extend
the stack before copying the list of files from an AV to the stack.

This fixes a regression introduced in 5.16.0.

MANIFEST

@@ -3748,6 +3748,7 @@ ext/File-Glob/t/basic.t		See if File::Glob works
 ext/File-Glob/t/case.t		See if File::Glob works
 ext/File-Glob/t/global.t	See if File::Glob works
 ext/File-Glob/TODO		File::Glob extension todo list
+ext/File-Glob/t/rt114984.t	See if File::Glob works
 ext/File-Glob/t/taint.t		See if File::Glob works
 ext/GDBM_File/GDBM_File.pm	GDBM extension Perl module
 ext/GDBM_File/GDBM_File.xs	GDBM extension external subroutines

ext/File-Glob/Glob.xs

@@ -93,6 +93,7 @@ iterate(pTHX_ bool(*globber)(pTHX_ AV *entries, SV *patsv))
     /* chuck it all out, quick or slow */
     if (gimme == G_ARRAY) {
 	if (!on_stack) {
+	    EXTEND(SP, AvFILLp(entries)+1);
 	    Copy(AvARRAY(entries), SP+1, AvFILLp(entries)+1, SV *);
 	    SP += AvFILLp(entries)+1;
 	}

ext/File-Glob/t/rt114984.t

@@ -0,0 +1,25 @@
+use strict;
+use warnings;
+use v5.16.0;
+use File::Temp 'tempdir';
+use File::Spec::Functions;
+use Test::More tests => 1;
+
+my @md = (1..305);
+my @mp = (1000..1205);
+
+my $path = tempdir uc cleanup => 1;
+
+foreach (@md) {
+    open(my $f, ">", catfile $path, "md_$_.dat");
+    close $f;
+}
+
+foreach (@mp) {
+    open(my $f, ">", catfile $path, "mp_$_.dat");
+    close $f;
+}
+my @b = glob(qq{$path/mp_[0123456789]*.dat
+                $path/md_[0123456789]*.dat});
+is scalar(@b), @md+@mp,
+    'File::Glob extends the stack when returning a long list';