diff --git a/libc/Android.bp b/libc/Android.bp
index 97146aa..c8df591 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -259,18 +259,20 @@
         // Include tzsetwall, timelocal, timegm, time2posix, and posix2time.
         "-DSTD_INSPIRED",
         // Obviously, we want to be thread-safe.
-        "-DTHREAD_SAFE",
+        "-DTHREAD_SAFE=1",
         // The name of the tm_gmtoff field in our struct tm.
         "-DTM_GMTOFF=tm_gmtoff",
         // Where we store our tzdata.
         "-DTZDIR=\"/system/usr/share/zoneinfo\"",
         // Include `tzname`, `timezone`, and `daylight` globals.
         "-DHAVE_POSIX_DECLS=0",
-        "-DUSG_COMPAT=1",
+        "-DUSG_COMPAT=2",
+        "-DHAVE_TZNAME=2",
+        // stdbool.h is available
+        "-DHAVE_STDBOOL_H",
         // Use the empty string (instead of "   ") as the timezone abbreviation
         // fallback.
         "-DWILDABBR=\"\"",
-        "-DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU",
         "-Dlint",
     ],