diff --git a/libc/arch-arm/cortex-a53/cortex-a53.mk b/libc/arch-arm/cortex-a53/cortex-a53.mk
new file mode 100644
index 0000000..b5c337c
--- /dev/null
+++ b/libc/arch-arm/cortex-a53/cortex-a53.mk
@@ -0,0 +1 @@
+include bionic/libc/arch-arm/cortex-a7/cortex-a7.mk
diff --git a/libc/arch-arm64/cortex-a53/cortex-a53.mk b/libc/arch-arm64/cortex-a53/cortex-a53.mk
new file mode 100644
index 0000000..676e886
--- /dev/null
+++ b/libc/arch-arm64/cortex-a53/cortex-a53.mk
@@ -0,0 +1 @@
+include bionic/libc/arch-arm64/generic/generic.mk
diff --git a/libc/include/sys/procfs.h b/libc/include/sys/procfs.h
index ef5b25f..b5b1a46 100644
--- a/libc/include/sys/procfs.h
+++ b/libc/include/sys/procfs.h
@@ -42,6 +42,9 @@
 typedef elf_gregset_t prgregset_t;
 typedef elf_fpregset_t prfpregset_t;
 
+typedef pid_t lwpid_t;
+typedef void* psaddr_t;
+
 __END_DECLS
 
 #endif /* _SYS_PROCFS_H_ */
diff --git a/libc/include/sys/ptrace.h b/libc/include/sys/ptrace.h
index 8bba9fe..4b881e7 100644
--- a/libc/include/sys/ptrace.h
+++ b/libc/include/sys/ptrace.h
@@ -34,11 +34,31 @@
 
 __BEGIN_DECLS
 
-/* glibc uses different names from the kernel for these two... */
+/* glibc uses different PTRACE_ names from the kernel for these two... */
 #define PTRACE_POKEUSER PTRACE_POKEUSR
 #define PTRACE_PEEKUSER PTRACE_PEEKUSR
 
-extern long ptrace(int, ...);
+/* glibc exports a different set of PT_ names too... */
+#define PT_TRACE_ME PTRACE_TRACEME
+#define PT_READ_I PTRACE_PEEKTEXT
+#define PT_READ_D PTRACE_PEEKDATA
+#define PT_READ_U PTRACE_PEEKUSR
+#define PT_WRITE_I PTRACE_POKETEXT
+#define PT_WRITE_D PTRACE_POKEDATA
+#define PT_WRITE_U PTRACE_POKEUSR
+#define PT_CONT PTRACE_CONT
+#define PT_KILL PTRACE_KILL
+#define PT_STEP PTRACE_SINGLESTEP
+#define PT_GETFPREGS PTRACE_GETFPREGS
+#define PT_ATTACH PTRACE_ATTACH
+#define PT_DETACH PTRACE_DETACH
+#define PT_SYSCALL PTRACE_SYSCALL
+#define PT_SETOPTIONS PTRACE_SETOPTIONS
+#define PT_GETEVENTMSG PTRACE_GETEVENTMSG
+#define PT_GETSIGINFO PTRACE_GETSIGINFO
+#define PT_SETSIGINFO PTRACE_SETSIGINFO
+
+long ptrace(int, ...);
 
 __END_DECLS
 
diff --git a/libc/include/sys/wait.h b/libc/include/sys/wait.h
index 8d9a5f6..12b7308 100644
--- a/libc/include/sys/wait.h
+++ b/libc/include/sys/wait.h
@@ -45,6 +45,9 @@
 #define WIFSTOPPED(s)   (WTERMSIG(s) == 0x7f)
 #define WIFSIGNALED(s)  (WTERMSIG((s)+1) >= 2)
 
+#define W_EXITCODE(ret, sig)    ((ret) << 8 | (sig))
+#define W_STOPCODE(sig)         ((sig) << 8 | 0x7f)
+
 extern pid_t  wait(int *);
 extern pid_t  waitpid(pid_t, int *, int);
 extern pid_t  wait4(pid_t, int *, int, struct rusage *);