diff --git a/pretty.c b/pretty.c
index acbfceb5fe..4da9a682f3 100644
--- a/pretty.c
+++ b/pretty.c
@@ -401,8 +401,14 @@ static const char *show_ident_date(const struct ident_split *ident,
 
 	if (ident->date_begin && ident->date_end)
 		date = strtoul(ident->date_begin, NULL, 10);
-	if (ident->tz_begin && ident->tz_end)
-		tz = strtol(ident->tz_begin, NULL, 10);
+	if (date_overflows(date))
+		date = 0;
+	else {
+		if (ident->tz_begin && ident->tz_end)
+			tz = strtol(ident->tz_begin, NULL, 10);
+		if (tz == LONG_MAX || tz == LONG_MIN)
+			tz = 0;
+	}
 	return show_date(date, tz, mode);
 }
 
diff --git a/t/t4212-log-corrupt.sh b/t/t4212-log-corrupt.sh
index 611b687a3c..80542d624b 100755
--- a/t/t4212-log-corrupt.sh
+++ b/t/t4212-log-corrupt.sh
@@ -60,4 +60,20 @@ test_expect_success 'unparsable dates produce sentinel value (%ad)' '
 	test_cmp expect actual
 '
 
+# date is 2^64 + 1
+test_expect_success 'date parser recognizes integer overflow' '
+	commit=$(munge_author_date HEAD 18446744073709551617) &&
+	echo "Thu Jan 1 00:00:00 1970 +0000" >expect &&
+	git log -1 --format=%ad $commit >actual &&
+	test_cmp expect actual
+'
+
+# date is 2^64 - 2
+test_expect_success 'date parser recognizes time_t overflow' '
+	commit=$(munge_author_date HEAD 18446744073709551614) &&
+	echo "Thu Jan 1 00:00:00 1970 +0000" >expect &&
+	git log -1 --format=%ad $commit >actual &&
+	test_cmp expect actual
+'
+
 test_done