RT#132347: fix building Tk

The Tk distribution has its own portability layer that expects to find
certain settings in %Config, as well as some cpp symbols defined in
perl.h. The recent Perl changes to require a C89 compiler caused some of
the metaconfig units defining those %Config settings and cpp symbols to
be omitted. This commit restores compatibility with Tk, by ensuring that
the things it wants are available even though they are no longer
provided by metaconfig.

1 files changed, 14 insertions, 1 deletions

diff --git a/configpm b/configpm
index 09b9e67aab..ebbaaa9b44 100755
--- a/configpm
+++ b/configpm
@@ -212,6 +212,19 @@ my $in_v     = 0;
 my %Data     = ();
 my $quote;
 
+# 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
+
 
 my %seen_quotes;
 {
@@ -567,7 +580,7 @@ $heavy_txt .= join('',
     map {
         /^([^=]+)/ ? [ $1, $_ ]
                    : [ $_, $_ ] # shouldnt happen
-    } @v_others
+    } @v_others, @v_forced
 ) . "!END!\n";
 
 # Only need the dynamic byteorder code in Config.pm if 'byteorder' is one of