diff --git a/libc/Android.mk b/libc/Android.mk
index 9610c14..d3dbe81 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -214,6 +215,7 @@ libc_bionic_src_:= \
     bionic/libc_init_common.cpp \
     bionic/libc_logging.cpp \
     bionic/libgen.cpp \
+    bionic/locale.cpp \
     bionic/mmap.cpp \
     bionic/pthread_attr.cpp \
     bionic/pthread_detach.cpp \
@@ -232,7 +232,6 @@ libc_bionic_src_files := \
     bionic/scandir.cpp \
     bionic/sched_getaffinity.cpp \
     bionic/__set_errno.cpp \
-    bionic/setlocale.cpp \
     bionic/signalfd.cpp \
     bionic/sigwait.cpp \
     bionic/statvfs.cpp \
diff --git a/libc/bionic/wchar.cpp b/libc/bionic/wchar.cpp
index 50a3875..cc830b7 100644
--- a/libc/bionic/wchar.cpp
+++ b/libc/bionic/wchar.cpp
@@ -96,6 +96,7 @@ int swscanf(const wchar_t* /*s*/, const wchar_t* /*format*/, ... ) {

 int iswalnum(wint_t wc) { return isalnum(wc); }
 int iswalpha(wint_t wc) { return isalpha(wc); }
+int iswblank(wint_t wc) { return isblank(wc); }
 int iswcntrl(wint_t wc) { return iscntrl(wc); }
 int iswdigit(wint_t wc) { return isdigit(wc); }
 int iswgraph(wint_t wc) { return isgraph(wc); }
diff --git a/libc/include/assert.h b/libc/include/assert.h
index 62470f5..361a5ff 100644
--- a/libc/include/assert.h
+++ b/libc/include/assert.h
@@ -60,6 +60,6 @@
 #endif

 __BEGIN_DECLS
-__dead void __assert(const char *, int, const char *);
-__dead void __assert2(const char *, int, const char *, const char *);
+__dead void __assert(const char *, int, const char *) __noreturn;
+__dead void __assert2(const char *, int, const char *, const char *) __noreturn;
 __END_DECLS
diff --git a/libc/include/ctype.h b/libc/include/ctype.h
index 5557e31..a66df12 100644
--- a/libc/include/ctype.h
+++ b/libc/include/ctype.h
@@ -45,11 +45,14 @@
 #define	_CTYPE_U	0x01
 #define	_CTYPE_L	0x02
 #define	_CTYPE_N	0x04
+#define	_CTYPE_D	0x04
 #define	_CTYPE_S	0x08
 #define	_CTYPE_P	0x10
 #define	_CTYPE_C	0x20
 #define	_CTYPE_X	0x40
 #define	_CTYPE_B	0x80
+#define	_CTYPE_R	(_CTYPE_P|_CTYPE_U|_CTYPE_L|_CTYPE_D|_CTYPE_B)
+#define	_CTYPE_A	(_CTYPE_L|_CTYPE_U)

 __BEGIN_DECLS

diff --git a/libc/include/locale.h b/libc/include/locale.h
index 65b5c7d..6989851 100644
--- a/libc/include/locale.h
+++ b/libc/include/locale.h
@@ -29,6 +29,7 @@
 #define _LOCALE_H_

 #include <sys/cdefs.h>
+#include <xlocale.h>

 __BEGIN_DECLS

@@ -43,17 +44,65 @@ enum {
     LC_PAPER     = 7,
     LC_NAME      = 8,
     LC_ADDRESS   = 9,
-
     LC_TELEPHONE      = 10,
     LC_MEASUREMENT    = 11,
     LC_IDENTIFICATION = 12
 };

-extern char *setlocale(int category, const char *locale);
+#define LC_CTYPE_MASK          (1 << LC_CTYPE)
+#define LC_NUMERIC_MASK        (1 << LC_NUMERIC)
+#define LC_TIME_MASK           (1 << LC_TIME)
+#define LC_COLLATE_MASK        (1 << LC_COLLATE)
+#define LC_MONETARY_MASK       (1 << LC_MONETARY)
+#define LC_MESSAGES_MASK       (1 << LC_MESSAGES)
+#define LC_PAPER_MASK          (1 << LC_PAPER)
+#define LC_NAME_MASK           (1 << LC_NAME)
+#define LC_ADDRESS_MASK        (1 << LC_ADDRESS)
+#define LC_TELEPHONE_MASK      (1 << LC_TELEPHONE)
+#define LC_MEASUREMENT_MASK    (1 << LC_MEASUREMENT)
+#define LC_IDENTIFICATION_MASK (1 << LC_IDENTIFICATION)
+
+#define LC_ALL_MASK (LC_CTYPE_MASK | LC_NUMERIC_MASK | LC_TIME_MASK | LC_COLLATE_MASK | \
+                     LC_MONETARY_MASK | LC_MESSAGES_MASK | LC_PAPER_MASK | LC_NAME_MASK | \
+                     LC_ADDRESS_MASK | LC_TELEPHONE_MASK | LC_MEASUREMENT_MASK | \
+                     LC_IDENTIFICATION_MASK)
+
+struct lconv {
+    char* decimal_point;
+    char* thousands_sep;
+    char* grouping;
+    char* int_curr_symbol;
+    char* currency_symbol;
+    char* mon_decimal_point;
+    char* mon_thousands_sep;
+    char* mon_grouping;
+    char* positive_sign;
+    char* negative_sign;
+    char  int_frac_digits;
+    char  frac_digits;
+    char  p_cs_precedes;
+    char  p_sep_by_space;
+    char  n_cs_precedes;
+    char  n_sep_by_space;
+    char  p_sign_posn;
+    char  n_sign_posn;
+    char  int_p_cs_precedes;
+    char  int_p_sep_by_space;
+    char  int_n_cs_precedes;
+    char  int_n_sep_by_space;
+    char  int_p_sign_posn;
+    char  int_n_sign_posn;
+};
+
+struct lconv* localeconv(void);
+
+locale_t duplocale(locale_t);
+void freelocale(locale_t);
+locale_t newlocale(int, const char*, locale_t);
+char* setlocale(int, const char*);
+locale_t uselocale(locale_t);

-/* Make libstdc++-v3 happy.  */
-struct lconv { };
-struct lconv *localeconv(void);
+#define LC_GLOBAL_LOCALE ((locale_t) -1L)

 __END_DECLS

diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 23fc944..28685c7 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -469,7 +469,10 @@ int vsprintf(char *dest, const char *format, __va_list ap)
 }

 #if defined(__clang__)
-#define snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__)
+  #if !defined(snprintf)
+    #define __wrap_snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__)
+    #define snprintf(...) __wrap_snprintf(__VA_ARGS__)
+  #endif
 #else
 __BIONIC_FORTIFY_INLINE
 __printflike(3, 4)
@@ -481,7 +484,10 @@ int snprintf(char *dest, size_t size, const char *format, ...)
 #endif

 #if defined(__clang__)
-#define sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__)
+  #if !defined(sprintf)
+    #define __wrap_sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__)
+    #define sprintf(...) __wrap_sprintf(__VA_ARGS__)
+  #endif
 #else
 __BIONIC_FORTIFY_INLINE
 __printflike(2, 3)
diff --git a/libc/include/stdlib.h b/libc/include/stdlib.h
index 9fa84c1..188da69 100644
--- a/libc/include/stdlib.h
+++ b/libc/include/stdlib.h
@@ -68,6 +68,10 @@ static __inline__ float strtof(const char *nptr, char **endptr)
     return (float)strtod(nptr, endptr);
 }

+static __inline__ long double strtold(const char* s, char** end_ptr) {
+  return (long double)strtod(s, end_ptr);
+}
+
 extern int atoi(const char *) __purefunc;
 extern long atol(const char *) __purefunc;
 extern long long atoll(const char *) __purefunc;
diff --git a/libc/include/wchar.h b/libc/include/wchar.h
index 76ac02c..c413806 100644
--- a/libc/include/wchar.h
+++ b/libc/include/wchar.h
@@ -77,6 +77,7 @@ extern int               fwprintf(FILE *, const wchar_t *, ...);
 extern int               fwscanf(FILE *, const wchar_t *, ...);
 extern int               iswalnum(wint_t);
 extern int               iswalpha(wint_t);
+extern int               iswblank(wint_t);
 extern int               iswcntrl(wint_t);
 extern int               iswdigit(wint_t);
 extern int               iswgraph(wint_t);