(decode_field_spec): Always give FIELD_INDEX a value.

This avoids spurious UMR from purify.
(prjoin): Add an assertion.
(add_field): Update assertion.

diff --git a/src/join.c b/src/join.c
index 666cd73e10d206bc3bca3d06dd8d417a8b11d63d..1c3494d8cb5e12b1eb1e065b14415a16433e3be6 100644 (file)
--- a/src/join.c
+++ b/src/join.c
@@ -460,6 +460,7 @@ prjoin (struct line *line1, struct line *line2)
          else
            {
              line = (o->file == 1 ? line1 : line2);
+             assert (o->field >= 0);
              field = o->field;
            }
          prfield (field, line);
@@ -630,7 +631,7 @@ add_field (int file, int field)
   struct outlist *o;
 
   assert (file == 0 || file == 1 || file == 2);
-  assert (field >= 0);
+  assert (file == 0 ? field < 0 : field >= 0);
 
   o = (struct outlist *) xmalloc (sizeof (struct outlist));
   o->file = file;
@@ -659,7 +660,8 @@ decode_field_spec (const char *s, int *file_index, int *field_index)
       if (s[1] == '\0')
        {
          *file_index = 0;
-         /* Leave *field_index undefined.  */
+         /* Give *field_index an invalid value.  */
+         *field_index = -1;
          invalid = 0;
        }
       else