1 file changed, 16 insertions, 2 deletions
diff --git a/source/parsing.c b/source/parsing.c
index dab81fa..71ecdb7 100644
--- a/source/parsing.c
+++ b/source/parsing.c
@@ -71,10 +71,24 @@ static void parse_user(const char *line, char **name, char **email, timestamp_t
 		strbuf_addch(&address, '>');
 		*email = strbuf_detach(&address, NULL);
 
+		// Clamped as git's own show_ident_date clamps them: a date past
+		// what the system can hold becomes the epoch, and a zone that is
+		// no hhmm offset becomes UTC, where git's date code would die on
+		// either and take the whole page with it.
 		if (ident.date_begin)
 			*date = parse_timestamp(ident.date_begin, NULL, 10);
-		if (ident.tz_begin)
-			*tz = atoi(ident.tz_begin);
+		if (date_overflows(*date))
+			*date = 0;
+		if (ident.tz_begin) {
+			long zone = strtol(ident.tz_begin, NULL, 10);
+			long west = zone < 0 ? -zone : 0;
+
+			*tz = zone > -10000 && zone < 10000 ? zone : 0;
+			// A date earlier than its own westward offset has no
+			// local time before the epoch to show.
+			if (*date < (timestamp_t)((west / 100) * 60 + west % 100) * 60)
+				*tz = 0;
+		}
 	}
 }