diff --git a/libc/bionic/time64.c b/libc/bionic/time64.c
index da38bf3..73f24ab 100644
--- a/libc/bionic/time64.c
+++ b/libc/bionic/time64.c
@@ -483,6 +483,11 @@
 }
 
 
+/* This implementation violates mktime specification, according to which
+   tm_yday, tm_wday, and tm_isdst fields should be updated. This function
+   leaves input_date unmodified. Given that there were no bug reports, fixing
+   it might cause more troubles than just leaving it as it is.
+ */
 Time64_T mktime64(const struct TM *input_date) {
     struct tm safe_date;
     struct TM date;