fmtutil: warn on shadowing formats

1 files changed, 16 insertions, 0 deletions

diff --git a/Master/texmf-dist/scripts/texlive/fmtutil.pl b/Master/texmf-dist/scripts/texlive/fmtutil.pl
index ca2eac40259..3882fc2a87e 100755
--- a/Master/texmf-dist/scripts/texlive/fmtutil.pl
+++ b/Master/texmf-dist/scripts/texlive/fmtutil.pl
@@ -587,12 +587,28 @@ sub select_and_rebuild_format {
     }
   }
   if ($doit) {
+    check_and_warn_on_user_format($fmt,$eng);
     return rebuild_one_format($fmt,$eng,$kpsefmt,$destdir,$fmtfile,$logfile);
   } else {
     return $FMT_NOTSELECTED;
   }
 }
 
+sub check_and_warn_on_user_format {
+  my ($fmt, $eng) = @_;
+  # do nothing if we are updating files in $TEXMFVAR
+  return if ($opts{'fmtdir'} eq $TEXMFVAR);
+  my $saved_fmtdir = $opts{'fmtdir'};
+  $opts{'fmtdir'} = "$TEXMFVAR/web2c";
+  my ($kpsefmt, $destdir, $fmtfile, $logfile) = compute_format_destination($fmt, $eng);
+  if (-r "$destdir/$fmtfile") {
+    print_deferred_warning("you have a shadowing format dump in TEXMFVAR for $fmt/$eng!!!\n");
+  }
+  $opts{'fmtdir'} = $saved_fmtdir;
+}
+  
+
+
 #  compute_format_destination
 # takes fmt/eng and returns the locations where format and log files
 # should be saved, that is, a list: (dump file full path, log file full path)