diff --git a/benchmarks/time_benchmark.cpp b/benchmarks/time_benchmark.cpp
index 0a146ae..22f6e8e 100644
--- a/benchmarks/time_benchmark.cpp
+++ b/benchmarks/time_benchmark.cpp
@@ -19,26 +19,6 @@
 #include <sys/syscall.h>
 #include <time.h>
 
-#if defined(__BIONIC__)
-
-// Used by the horrible android.text.format.Time class, which is used by Calendar. http://b/8270865.
-extern "C" void localtime_tz(const time_t* const timep, struct tm* tmp, const char* tz);
-
-static void BM_time_localtime_tz(int iters) {
-  StartBenchmarkTiming();
-
-  time_t now(time(NULL));
-  tm broken_down_time;
-  for (int i = 0; i < iters; ++i) {
-    localtime_tz(&now, &broken_down_time, "Europe/Berlin");
-  }
-
-  StopBenchmarkTiming();
-}
-BENCHMARK(BM_time_localtime_tz);
-
-#endif
-
 static void BM_time_clock_gettime(int iters) {
   StartBenchmarkTiming();
 
diff --git a/libc/include/sys/cdefs_elf.h b/libc/include/sys/cdefs_elf.h
index b5db13e..4dd7dc3 100644
--- a/libc/include/sys/cdefs_elf.h
+++ b/libc/include/sys/cdefs_elf.h
@@ -68,7 +68,7 @@
 #ifdef __LP64__
 #define __LIBC64_HIDDEN__ __LIBC_HIDDEN__
 #else
-#define __LIBC64_HIDDEN__
+#define __LIBC64_HIDDEN__ __LIBC_ABI_PUBLIC__
 #endif
 
 /* Used to tag non-static symbols that are public and exposed by the shared library. */
diff --git a/libc/private/bionic_time.h b/libc/private/bionic_time.h
index ca5c146..030dcfd 100644
--- a/libc/private/bionic_time.h
+++ b/libc/private/bionic_time.h
@@ -33,32 +33,8 @@
 
 __BEGIN_DECLS
 
-#ifndef _BIONIC_STRFTIME_TZ_DECLARED
-#define _BIONIC_STRFTIME_TZ_DECLARED
-
-struct strftime_locale {
-    const char *  mon[12];
-    const char *  month[12];
-    const char *  standalone_month[12];
-    const char *  wday[7];
-    const char *  weekday[7];
-    const char *  X_fmt;
-    const char *  x_fmt;
-    const char *  c_fmt;
-    const char *  am;
-    const char *  pm;
-    const char *  date_fmt;
-};
-
-/*
- * Note: you should consider these extensions deprecated and use managed code or icu4c instead.
- * We'd like to hide them but they're currently still used in frameworks code.
- */
-extern size_t strftime_tz(char*, size_t, const char*, const struct tm*, const struct strftime_locale*);
-extern time_t mktime_tz(struct tm* const, char const*);
-extern void localtime_tz(const time_t* const, struct tm*, const char*);
-
-#endif /* _BIONIC_STRFTIME_TZ_DECLARED */
+// We can't remove this (and this file) until we fix MtpUtils.cpp.
+time_t mktime_tz(struct tm* const, char const*);
 
 __END_DECLS
 
diff --git a/libc/tzcode/localtime.c b/libc/tzcode/localtime.c
index 4dd7ab0..2e6804e 100644
--- a/libc/tzcode/localtime.c
+++ b/libc/tzcode/localtime.c
@@ -2293,7 +2293,8 @@
 }
 
 // Non-standard API: mktime(3) but with an explicit timezone parameter.
-time_t __attribute__((visibility("default"))) mktime_tz(struct tm* const tmp, const char* tz) {
+// This can't actually be hidden/removed until we fix MtpUtils.cpp
+__attribute__((visibility("default"))) time_t mktime_tz(struct tm* const tmp, const char* tz) {
   struct state* st = malloc(sizeof(*st));
   time_t return_value;
 
@@ -2310,7 +2311,8 @@
 }
 
 // Non-standard API: localtime(3) but with an explicit timezone parameter.
-void __attribute__((visibility("default"))) localtime_tz(const time_t* const timep, struct tm* tmp, const char* tz) {
+#if !defined(__LP64__)
+__attribute__((visibility("default"))) void localtime_tz(const time_t* const timep, struct tm* tmp, const char* tz) {
   struct state* st = malloc(sizeof(*st));
 
   if (st == NULL)
@@ -2322,5 +2324,6 @@
   localsub(timep, 0L, tmp, st);
   free(st);
 }
+#endif
 
 // END android-added
diff --git a/libc/tzcode/strftime.c b/libc/tzcode/strftime.c
index f996f48..c4ff198 100644
--- a/libc/tzcode/strftime.c
+++ b/libc/tzcode/strftime.c
@@ -29,16 +29,38 @@
 #include "locale.h"
 
 #if __ANDROID__
-/* Android: struct lc_time_T is defined as strftime_locale in "bionic_time.h" */
-#include "private/bionic_time.h"  /* for strftime_tz */
-#define  lc_time_T    strftime_locale
+
+/*
+ * This has an extra standalone_month array field compared to upstream.
+ * We only need to keep that if we leave the strftime_tz symbol exposed.
+ * Even then, this structure was never in an NDK header file.
+ */
+struct lc_time_T {
+  const char *  mon[12];
+  const char *  month[12];
+  const char *  standalone_month[12];
+  const char *  wday[7];
+  const char *  weekday[7];
+  const char *  X_fmt;
+  const char *  x_fmt;
+  const char *  c_fmt;
+  const char *  am;
+  const char *  pm;
+  const char *  date_fmt;
+};
+
+/* LP32 had a 32-bit time_t, so we need to work around that here. */
 #if defined(__LP64__)
 #define time64_t time_t
 #define mktime64 mktime
 #else
 #include <time64.h>
 #endif
+
 #include <ctype.h>
+
+size_t strftime_tz(char*, size_t, const char*, const struct tm*, const struct lc_time_T*);
+
 #else // not __ANDROID__
 struct lc_time_T {
     const char *    mon[MONSPERYEAR];
@@ -116,7 +138,7 @@
 static char *   _add(const char *, char *, const char *, int);
 static char *   _conv(int, const char *, char *, const char *);
 static char *   _fmt(const char *, const struct tm *, char *, const char *,
-            int *, const struct strftime_locale*);
+            int *, const struct lc_time_T*);
 static char *   _yconv(int, int, int, int, char *, const char *, int);
 static char *   getformat(int, char *, char *, char *, char *);
 
@@ -143,13 +165,12 @@
     return strftime_tz(s, maxsize, format, t, Locale);
 }
 
-size_t
-__attribute__((visibility("default"))) strftime_tz(s, maxsize, format, t, locale)
+__LIBC64_HIDDEN__ size_t strftime_tz(s, maxsize, format, t, locale)
 char * const        s;
 const size_t        maxsize;
 const char * const  format;
 const struct tm * const t;
-const struct strftime_locale *locale;
+const struct lc_time_T *locale;
 {
     char *  p;
     int warn;
@@ -202,7 +223,7 @@
 char *          pt;
 const char * const  ptlim;
 int *           warnp;
-const struct strftime_locale* locale;
+const struct lc_time_T* locale;
 {
     for ( ; *format; ++format) {
         if (*format == '%') {
diff --git a/tests/time_test.cpp b/tests/time_test.cpp
index 12b1ea7..241c4a0 100644
--- a/tests/time_test.cpp
+++ b/tests/time_test.cpp
@@ -27,34 +27,6 @@
 
 #include "ScopedSignalHandler.h"
 
-#if defined(__BIONIC__) // mktime_tz is a bionic extension.
-#include <libc/private/bionic_time.h>
-#endif // __BIONIC__
-
-TEST(time, mktime_tz) {
-#if defined(__BIONIC__)
-  struct tm epoch;
-  memset(&epoch, 0, sizeof(tm));
-  epoch.tm_year = 1970 - 1900;
-  epoch.tm_mon = 1;
-  epoch.tm_mday = 1;
-
-  // Alphabetically first. Coincidentally equivalent to UTC.
-  ASSERT_EQ(2678400, mktime_tz(&epoch, "Africa/Abidjan"));
-
-  // Alphabetically last. Coincidentally equivalent to UTC.
-  ASSERT_EQ(2678400, mktime_tz(&epoch, "Zulu"));
-
-  // Somewhere in the middle, not UTC.
-  ASSERT_EQ(2707200, mktime_tz(&epoch, "America/Los_Angeles"));
-
-  // Missing. Falls back to UTC.
-  ASSERT_EQ(2678400, mktime_tz(&epoch, "PST"));
-#else // __BIONIC__
-  GTEST_LOG_(INFO) << "This test does nothing.\n";
-#endif // __BIONIC__
-}
-
 TEST(time, gmtime) {
   time_t t = 0;
   tm* broken_down = gmtime(&t);
@@ -108,9 +80,6 @@
 #if !defined(__LP64__)
   // 32-bit bionic stupidly had a signed 32-bit time_t.
   ASSERT_EQ(-1, mktime(&t));
-#if defined(__BIONIC__)
-  ASSERT_EQ(-1, mktime_tz(&t, "UTC"));
-#endif
 #else
   // Everyone else should be using a signed 64-bit time_t.
   ASSERT_GE(sizeof(time_t) * 8, 64U);
@@ -118,16 +87,10 @@
   setenv("TZ", "America/Los_Angeles", 1);
   tzset();
   ASSERT_EQ(static_cast<time_t>(4108348800U), mktime(&t));
-#if defined(__BIONIC__)
-  ASSERT_EQ(static_cast<time_t>(4108320000U), mktime_tz(&t, "UTC"));
-#endif
 
   setenv("TZ", "UTC", 1);
   tzset();
   ASSERT_EQ(static_cast<time_t>(4108320000U), mktime(&t));
-#if defined(__BIONIC__)
-  ASSERT_EQ(static_cast<time_t>(4108348800U), mktime_tz(&t, "America/Los_Angeles"));
-#endif
 #endif
 }