tag: error when git-column fails

If the user asks for the list of tags to be displayed in columns
("--columns"), a child git-column process is used to format the output
as expected.

In a rare situation where we encounter a problem spawning that child
process, we will work erroneously.

Make noticeable we're having a problem executing git-column, so the user
can act accordingly.

Signed-off-by: Rubén Justo <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: rjusto

builtin/tag.c

@@ -537,7 +537,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 			struct column_options copts;
 			memset(&copts, 0, sizeof(copts));
 			copts.padding = 2;
-			run_column_filter(colopts, &copts);
+			if (run_column_filter(colopts, &copts))
+				die(_("could not start 'git column'"));
 		}
 		filter.name_patterns = argv;
 		ret = list_tags(&filter, sorting, &format);