1 files changed, 8 insertions, 2 deletions
diff --git a/Master/texmf/scripts/texlive/tlmgr.pl b/Master/texmf/scripts/texlive/tlmgr.pl
index 3d26f91b238..4f5bdae1a53 100755
--- a/Master/texmf/scripts/texlive/tlmgr.pl
+++ b/Master/texmf/scripts/texlive/tlmgr.pl
@@ -2980,10 +2980,16 @@ sub action_generate {
 
   if ($what =~ m/^language(\.dat|\.def)?$/i) {
     #
+    # if --rebuild-sys is given *and* --dest we warn that this might not
+    # work if the destination is not the default one
+    if ($opts{"rebuild-sys"} && $dest) {
+      tlwarn("tlmgr generate $what: --rebuild-sys and --dest given.\n");
+      tlwarn("The call to fmtutil-sys can fail if the given destination does\n");
+      tlwarn("not conincide with the default one.\n");
+    }
+    #
     # we have to set TEXMFVAR, TEXMFCONFIG in the environment so that
     # searching for language.(dat/def) does search in the right place
-    my $ldat;
-    my $ldef;
     if ($what =~ m/^language(\.dat)?$/i) {
       $dest ||= "$TEXMFSYSVAR/tex/generic/config/language.dat";
       $localconf ||= "$TEXMFLOCAL/tex/generic/config/language-local.dat";