+# These variables were set in older versions of Perl, but are no longer needed
+# by the core. However, some CPAN modules may rely on them; in particular, Tk
+# (at least up to version 804.034) fails to build without them. We force them
+# to be emitted to Config_heavy.pl for backcompat with such modules (and we may
+# find that this set needs to be extended in future). See RT#132347.
+my @v_forced = map "$_\n", split /\n+/, <<'EOT';
+i_limits='define'
+i_stdlib='define'
+i_string='define'
+i_time='define'
+prototype='define'
+EOT
+