diff --git a/libc/Android.mk b/libc/Android.mk
index 88be78d..417d0ab 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -246,6 +246,7 @@
     bionic/seteuid.cpp \
     bionic/setlocale.cpp \
     bionic/signalfd.cpp \
+    bionic/sigpending.cpp \
     bionic/sigprocmask.cpp \
     bionic/sigsuspend.cpp \
     bionic/sigwait.cpp \
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 1d6c75f..f5712e1 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -28,13 +28,12 @@
 void    _exit:exit_group(int)      all
 void    _exit_thread:exit(int)     all
 pid_t   __fork:fork(void)           all
-pid_t   _waitpid:waitpid(pid_t, int*, int, struct rusage*)   mips,x86
-int     __waitid:waitid(int, pid_t, struct siginfo_t*, int, void*)          all
 pid_t   wait4(pid_t pid, int* status, int options, struct rusage* rusage)   all
 
-# NOTE: this system call is never called directly, but we list it there
-#       to have __NR_clone properly defined.
+# NOTE: these stubs are unused.
 pid_t   __sys_clone:clone(int, void*, int*, void*, int*) all
+pid_t   _waitpid:waitpid(pid_t, int*, int, struct rusage*)   mips,x86
+int     __waitid:waitid(int, pid_t, struct siginfo_t*, int, void*)          all
 
 int     execve(const char*, char* const*, char* const*)  all
 
@@ -226,8 +225,8 @@
 
 # signals
 int     sigaction(int, const struct sigaction*, struct sigaction*)  arm,x86,mips
-int     sigpending(sigset_t*)  arm,x86,mips
 int     __rt_sigaction:rt_sigaction(int, const struct sigaction*, struct sigaction*, size_t)  all
+int     __rt_sigpending:rt_sigpending(sigset_t*, size_t)  all
 int     __rt_sigprocmask:rt_sigprocmask(int, const sigset_t*, sigset_t*, size_t)  all
 int     __rt_sigsuspend:rt_sigsuspend(const sigset_t*, size_t)  all
 int     __rt_sigtimedwait:rt_sigtimedwait(const sigset_t*, struct siginfo_t*, struct timespec_t*, size_t)  all
diff --git a/libc/arch-arm/syscalls.mk b/libc/arch-arm/syscalls.mk
index dc7e3df..5e5e56b 100644
--- a/libc/arch-arm/syscalls.mk
+++ b/libc/arch-arm/syscalls.mk
@@ -3,9 +3,9 @@
 syscall_src += arch-arm/syscalls/_exit.S
 syscall_src += arch-arm/syscalls/_exit_thread.S
 syscall_src += arch-arm/syscalls/__fork.S
-syscall_src += arch-arm/syscalls/__waitid.S
 syscall_src += arch-arm/syscalls/wait4.S
 syscall_src += arch-arm/syscalls/__sys_clone.S
+syscall_src += arch-arm/syscalls/__waitid.S
 syscall_src += arch-arm/syscalls/execve.S
 syscall_src += arch-arm/syscalls/getuid.S
 syscall_src += arch-arm/syscalls/getgid.S
@@ -152,8 +152,8 @@
 syscall_src += arch-arm/syscalls/timerfd_settime.S
 syscall_src += arch-arm/syscalls/timerfd_gettime.S
 syscall_src += arch-arm/syscalls/sigaction.S
-syscall_src += arch-arm/syscalls/sigpending.S
 syscall_src += arch-arm/syscalls/__rt_sigaction.S
+syscall_src += arch-arm/syscalls/__rt_sigpending.S
 syscall_src += arch-arm/syscalls/__rt_sigprocmask.S
 syscall_src += arch-arm/syscalls/__rt_sigsuspend.S
 syscall_src += arch-arm/syscalls/__rt_sigtimedwait.S
diff --git a/libc/arch-arm/syscalls/sigpending.S b/libc/arch-arm/syscalls/__rt_sigpending.S
similarity index 76%
rename from libc/arch-arm/syscalls/sigpending.S
rename to libc/arch-arm/syscalls/__rt_sigpending.S
index ba667a0..0e0be3a 100644
--- a/libc/arch-arm/syscalls/sigpending.S
+++ b/libc/arch-arm/syscalls/__rt_sigpending.S
@@ -3,13 +3,13 @@
 #include <linux/err.h>
 #include <machine/asm.h>
 
-ENTRY(sigpending)
+ENTRY(__rt_sigpending)
     mov     ip, r7
-    ldr     r7, =__NR_sigpending
+    ldr     r7, =__NR_rt_sigpending
     swi     #0
     mov     r7, ip
     cmn     r0, #(MAX_ERRNO + 1)
     bxls    lr
     neg     r0, r0
     b       __set_errno
-END(sigpending)
+END(__rt_sigpending)
diff --git a/libc/arch-mips/syscalls.mk b/libc/arch-mips/syscalls.mk
index 2704200..7d99dad 100644
--- a/libc/arch-mips/syscalls.mk
+++ b/libc/arch-mips/syscalls.mk
@@ -3,10 +3,10 @@
 syscall_src += arch-mips/syscalls/_exit.S
 syscall_src += arch-mips/syscalls/_exit_thread.S
 syscall_src += arch-mips/syscalls/__fork.S
-syscall_src += arch-mips/syscalls/_waitpid.S
-syscall_src += arch-mips/syscalls/__waitid.S
 syscall_src += arch-mips/syscalls/wait4.S
 syscall_src += arch-mips/syscalls/__sys_clone.S
+syscall_src += arch-mips/syscalls/_waitpid.S
+syscall_src += arch-mips/syscalls/__waitid.S
 syscall_src += arch-mips/syscalls/execve.S
 syscall_src += arch-mips/syscalls/getuid.S
 syscall_src += arch-mips/syscalls/getgid.S
@@ -155,8 +155,8 @@
 syscall_src += arch-mips/syscalls/timerfd_settime.S
 syscall_src += arch-mips/syscalls/timerfd_gettime.S
 syscall_src += arch-mips/syscalls/sigaction.S
-syscall_src += arch-mips/syscalls/sigpending.S
 syscall_src += arch-mips/syscalls/__rt_sigaction.S
+syscall_src += arch-mips/syscalls/__rt_sigpending.S
 syscall_src += arch-mips/syscalls/__rt_sigprocmask.S
 syscall_src += arch-mips/syscalls/__rt_sigsuspend.S
 syscall_src += arch-mips/syscalls/__rt_sigtimedwait.S
diff --git a/libc/arch-mips/syscalls/sigpending.S b/libc/arch-mips/syscalls/__rt_sigpending.S
similarity index 66%
rename from libc/arch-mips/syscalls/sigpending.S
rename to libc/arch-mips/syscalls/__rt_sigpending.S
index 45baa4f..bd4a96e 100644
--- a/libc/arch-mips/syscalls/sigpending.S
+++ b/libc/arch-mips/syscalls/__rt_sigpending.S
@@ -1,14 +1,14 @@
 /* autogenerated by gensyscalls.py */
 #include <asm/unistd.h>
     .text
-    .globl sigpending
+    .globl __rt_sigpending
     .align 4
-    .ent sigpending
+    .ent __rt_sigpending
 
-sigpending:
+__rt_sigpending:
     .set noreorder
     .cpload $t9
-    li $v0, __NR_sigpending
+    li $v0, __NR_rt_sigpending
     syscall
     bnez $a3, 1f
     move $a0, $v0
@@ -19,4 +19,4 @@
     j $t9
     nop
     .set reorder
-    .end sigpending
+    .end __rt_sigpending
diff --git a/libc/arch-x86/syscalls.mk b/libc/arch-x86/syscalls.mk
index 10970a6..698f6f5 100644
--- a/libc/arch-x86/syscalls.mk
+++ b/libc/arch-x86/syscalls.mk
@@ -3,10 +3,10 @@
 syscall_src += arch-x86/syscalls/_exit.S
 syscall_src += arch-x86/syscalls/_exit_thread.S
 syscall_src += arch-x86/syscalls/__fork.S
-syscall_src += arch-x86/syscalls/_waitpid.S
-syscall_src += arch-x86/syscalls/__waitid.S
 syscall_src += arch-x86/syscalls/wait4.S
 syscall_src += arch-x86/syscalls/__sys_clone.S
+syscall_src += arch-x86/syscalls/_waitpid.S
+syscall_src += arch-x86/syscalls/__waitid.S
 syscall_src += arch-x86/syscalls/execve.S
 syscall_src += arch-x86/syscalls/getuid.S
 syscall_src += arch-x86/syscalls/getgid.S
@@ -156,8 +156,8 @@
 syscall_src += arch-x86/syscalls/timerfd_settime.S
 syscall_src += arch-x86/syscalls/timerfd_gettime.S
 syscall_src += arch-x86/syscalls/sigaction.S
-syscall_src += arch-x86/syscalls/sigpending.S
 syscall_src += arch-x86/syscalls/__rt_sigaction.S
+syscall_src += arch-x86/syscalls/__rt_sigpending.S
 syscall_src += arch-x86/syscalls/__rt_sigprocmask.S
 syscall_src += arch-x86/syscalls/__rt_sigsuspend.S
 syscall_src += arch-x86/syscalls/__rt_sigtimedwait.S
diff --git a/libc/arch-x86/syscalls/sigpending.S b/libc/arch-x86/syscalls/__rt_sigpending.S
similarity index 65%
rename from libc/arch-x86/syscalls/sigpending.S
rename to libc/arch-x86/syscalls/__rt_sigpending.S
index 70c3ec4..84634b4 100644
--- a/libc/arch-x86/syscalls/sigpending.S
+++ b/libc/arch-x86/syscalls/__rt_sigpending.S
@@ -3,10 +3,12 @@
 #include <linux/err.h>
 #include <machine/asm.h>
 
-ENTRY(sigpending)
+ENTRY(__rt_sigpending)
     pushl   %ebx
-    mov     8(%esp), %ebx
-    movl    $__NR_sigpending, %eax
+    pushl   %ecx
+    mov     12(%esp), %ebx
+    mov     16(%esp), %ecx
+    movl    $__NR_rt_sigpending, %eax
     int     $0x80
     cmpl    $-MAX_ERRNO, %eax
     jb      1f
@@ -16,6 +18,7 @@
     addl    $4, %esp
     orl     $-1, %eax
 1:
+    popl    %ecx
     popl    %ebx
     ret
-END(sigpending)
+END(__rt_sigpending)
diff --git a/libc/arch-x86_64/syscalls.mk b/libc/arch-x86_64/syscalls.mk
index 6b72ca0..611bb35 100644
--- a/libc/arch-x86_64/syscalls.mk
+++ b/libc/arch-x86_64/syscalls.mk
@@ -3,9 +3,9 @@
 syscall_src += arch-x86_64/syscalls/_exit.S
 syscall_src += arch-x86_64/syscalls/_exit_thread.S
 syscall_src += arch-x86_64/syscalls/__fork.S
-syscall_src += arch-x86_64/syscalls/__waitid.S
 syscall_src += arch-x86_64/syscalls/wait4.S
 syscall_src += arch-x86_64/syscalls/__sys_clone.S
+syscall_src += arch-x86_64/syscalls/__waitid.S
 syscall_src += arch-x86_64/syscalls/execve.S
 syscall_src += arch-x86_64/syscalls/getuid.S
 syscall_src += arch-x86_64/syscalls/getgid.S
@@ -150,6 +150,7 @@
 syscall_src += arch-x86_64/syscalls/timerfd_settime.S
 syscall_src += arch-x86_64/syscalls/timerfd_gettime.S
 syscall_src += arch-x86_64/syscalls/__rt_sigaction.S
+syscall_src += arch-x86_64/syscalls/__rt_sigpending.S
 syscall_src += arch-x86_64/syscalls/__rt_sigprocmask.S
 syscall_src += arch-x86_64/syscalls/__rt_sigsuspend.S
 syscall_src += arch-x86_64/syscalls/__rt_sigtimedwait.S
diff --git a/libc/arch-x86_64/syscalls/__rt_sigpending.S b/libc/arch-x86_64/syscalls/__rt_sigpending.S
new file mode 100644
index 0000000..ecf1971
--- /dev/null
+++ b/libc/arch-x86_64/syscalls/__rt_sigpending.S
@@ -0,0 +1,17 @@
+/* autogenerated by gensyscalls.py */
+#include <asm/unistd.h>
+#include <linux/err.h>
+#include <machine/asm.h>
+
+ENTRY(__rt_sigpending)
+    movl    $__NR_rt_sigpending, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno
+    orq     $-1, %rax
+1:
+    ret
+END(__rt_sigpending)
diff --git a/libc/bionic/sigpending.cpp b/libc/bionic/sigpending.cpp
new file mode 100644
index 0000000..b6e503c
--- /dev/null
+++ b/libc/bionic/sigpending.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <signal.h>
+
+#include "private/kernel_sigset_t.h"
+
+extern "C" int __rt_sigpending(const kernel_sigset_t*, size_t);
+
+int sigpending(sigset_t* bionic_set) {
+  kernel_sigset_t set;
+  int result = __rt_sigpending(&set, sizeof(set));
+  if (result != -1) {
+    *bionic_set = set.bionic;
+  }
+  return result;
+}
diff --git a/libc/include/signal.h b/libc/include/signal.h
index 15d2d3a..e211ef7 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -122,24 +122,20 @@
     return bsd_signal(s,f);
 }
 
-/* the syscall itself */
-extern __sighandler_t __signal(int, __sighandler_t, int);
-
-extern int sigprocmask(int, const sigset_t *, sigset_t *);
-extern int sigaction(int, const struct sigaction *, struct sigaction *);
-
-extern int sigpending(sigset_t *);
-extern int sigsuspend(const sigset_t *);
-extern int sigwait(const sigset_t *set, int *sig);
-extern int siginterrupt(int  sig, int  flag);
+extern int sigaction(int, const struct sigaction*, struct sigaction*);
+extern int siginterrupt(int, int);
+extern int sigpending(sigset_t*) __nonnull((1));
+extern int sigprocmask(int, const sigset_t*, sigset_t*);
+extern int sigsuspend(const sigset_t*) __nonnull((1));
+extern int sigwait(const sigset_t*, int*) __nonnull((1, 2));
 
 extern int raise(int);
 extern int kill(pid_t, int);
-extern int killpg(int pgrp, int sig);
-extern int sigaltstack(const stack_t *ss, stack_t *oss);
+extern int killpg(int, int);
+extern int sigaltstack(const stack_t*, stack_t*);
 
-extern void psiginfo(const siginfo_t* si, const char* message);
-extern void psignal(int signal_number, const char* message);
+extern void psiginfo(const siginfo_t*, const char*);
+extern void psignal(int, const char*);
 
 __END_DECLS