Export of internal Abseil changes -- 4b566a7deeba5db473c83f4924c1d182a002779f by Abseil Team <absl-team@google.com>: Add absl::LeakCheckerIsActive to check whether a leak checker is built into the target and enabled. For LeakSanitizer, it is by default enabled unless __lsan_is_turned_off() is defined and returns true. PiperOrigin-RevId: 364654465 -- 0a56ff5310b66f9d1ff5e5e2a053335ecfb5c75b by Abseil Team <absl-team@google.com>: Update absl::FromTM documentation to reflect implementation. PiperOrigin-RevId: 364388743 GitOrigin-RevId: 4b566a7deeba5db473c83f4924c1d182a002779f Change-Id: I8df35b761b532e79d620f484153083c3499ef55b

diff --git a/absl/time/time.h b/absl/time/time.h
index d9ad1ae..2df6858 100644
--- a/absl/time/time.h
+++ b/absl/time/time.h

@@ -1180,11 +1180,15 @@
 //
 // Converts the `tm_year`, `tm_mon`, `tm_mday`, `tm_hour`, `tm_min`, and
 // `tm_sec` fields to an `absl::Time` using the given time zone. See ctime(3)
-// for a description of the expected values of the tm fields. If the indicated
-// time instant is not unique (see `absl::TimeZone::At(absl::CivilSecond)`
-// above), the `tm_isdst` field is consulted to select the desired instant
-// (`tm_isdst` > 0 means DST, `tm_isdst` == 0 means no DST, `tm_isdst` < 0
-// means use the post-transition offset).
+// for a description of the expected values of the tm fields. If the civil time
+// is unique (see `absl::TimeZone::At(absl::CivilSecond)` above), the matching
+// time instant is returned.  Otherwise, the `tm_isdst` field is consulted to
+// choose between the possible results.  For a repeated civil time, `tm_isdst !=
+// 0` returns the matching DST instant, while `tm_isdst == 0` returns the
+// matching non-DST instant.  For a skipped civil time there is no matching
+// instant, so `tm_isdst != 0` returns the DST instant, and `tm_isdst == 0`
+// returns the non-DST instant, that would have matched if the transition never
+// happened.
 Time FromTM(const struct tm& tm, TimeZone tz);
 
 // ToTM()