diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 063b51d..3656733 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -79,6 +79,8 @@
 #define __BIONIC_CAST(_k,_t,_v) ((_t) (_v))
 #endif
 
+#define __BIONIC_ALIGN(__value, __alignment) (((__value) + (__alignment)-1) & ~((__alignment)-1))
+
 /*
  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
diff --git a/libc/include/sys/mman.h b/libc/include/sys/mman.h
index 1e752c4..83b5e6f 100644
--- a/libc/include/sys/mman.h
+++ b/libc/include/sys/mman.h
@@ -45,12 +45,19 @@
 #define MREMAP_FIXED    2
 
 #if defined(__USE_FILE_OFFSET64)
-void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset) __RENAME(mmap64) __INTRODUCED_IN(21);
+/*
+ * mmap64 wasn't really around until L, but we added an inline for it since it
+ * allows a lot more code to compile with _FILE_OFFSET_BITS=64.
+ */
+void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset)
+    __RENAME(mmap64);
 #else
 void* mmap(void* __addr, size_t __size, int __prot, int __flags, int __fd, off_t __offset);
 #endif
 
+#if __ANDROID_API__ >= __ANDROID_API_L__
 void* mmap64(void* __addr, size_t __size, int __prot, int __flags, int __fd, off64_t __offset) __INTRODUCED_IN(21);
+#endif
 
 int munmap(void* __addr, size_t __size);
 int msync(void* __addr, size_t __size, int __flags);
@@ -86,4 +93,6 @@
 
 __END_DECLS
 
+#include <android/legacy_sys_mman_inlines.h>
+
 #endif