diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h
index c199ade..d2f5aa0 100644
--- a/tools/include/nolibc/nolibc.h
+++ b/tools/include/nolibc/nolibc.h
@@ -116,6 +116,7 @@
 #include "sched.h"
 #include "signal.h"
 #include "unistd.h"
+#include "stdbool.h"
 #include "stdio.h"
 #include "stdlib.h"
 #include "string.h"
diff --git a/tools/include/nolibc/poll.h b/tools/include/nolibc/poll.h
index 1765acb..0d053f9 100644
--- a/tools/include/nolibc/poll.h
+++ b/tools/include/nolibc/poll.h
@@ -39,10 +39,8 @@ int sys_poll(struct pollfd *fds, int nfds, int timeout)
 		t.tv_nsec = (timeout % 1000) * 1000000;
 	}
 	return my_syscall5(__NR_ppoll_time64, fds, nfds, (timeout >= 0) ? &t : NULL, NULL, 0);
-#elif defined(__NR_poll)
-	return my_syscall3(__NR_poll, fds, nfds, timeout);
 #else
-	return __nolibc_enosys(__func__, fds, nfds, timeout);
+	return my_syscall3(__NR_poll, fds, nfds, timeout);
 #endif
 }
 
diff --git a/tools/include/nolibc/std.h b/tools/include/nolibc/std.h
index ba950f0..2c1ad23 100644
--- a/tools/include/nolibc/std.h
+++ b/tools/include/nolibc/std.h
@@ -29,6 +29,6 @@ typedef unsigned long       nlink_t;
 typedef   signed long         off_t;
 typedef   signed long     blksize_t;
 typedef   signed long      blkcnt_t;
-typedef __kernel_old_time_t  time_t;
+typedef __kernel_time_t      time_t;
 
 #endif /* _NOLIBC_STD_H */
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h
index 295e71d..c5564f5 100644
--- a/tools/include/nolibc/sys.h
+++ b/tools/include/nolibc/sys.h
@@ -142,10 +142,8 @@ int sys_chmod(const char *path, mode_t mode)
 {
 #if defined(__NR_fchmodat)
 	return my_syscall4(__NR_fchmodat, AT_FDCWD, path, mode, 0);
-#elif defined(__NR_chmod)
-	return my_syscall2(__NR_chmod, path, mode);
 #else
-	return __nolibc_enosys(__func__, path, mode);
+	return my_syscall2(__NR_chmod, path, mode);
 #endif
 }
 
@@ -165,10 +163,8 @@ int sys_chown(const char *path, uid_t owner, gid_t group)
 {
 #if defined(__NR_fchownat)
 	return my_syscall5(__NR_fchownat, AT_FDCWD, path, owner, group, 0);
-#elif defined(__NR_chown)
-	return my_syscall3(__NR_chown, path, owner, group);
 #else
-	return __nolibc_enosys(__func__, path, owner, group);
+	return my_syscall3(__NR_chown, path, owner, group);
 #endif
 }
 
@@ -238,11 +234,22 @@ static __attribute__((unused))
 int sys_dup2(int old, int new)
 {
 #if defined(__NR_dup3)
+	int ret, nr_fcntl;
+
+#ifdef __NR_fcntl64
+	nr_fcntl = __NR_fcntl64;
+#else
+	nr_fcntl = __NR_fcntl;
+#endif
+
+	if (old == new) {
+		ret = my_syscall2(nr_fcntl, old, F_GETFD);
+		return ret < 0 ? ret : old;
+	}
+
 	return my_syscall3(__NR_dup3, old, new, 0);
-#elif defined(__NR_dup2)
-	return my_syscall2(__NR_dup2, old, new);
 #else
-	return __nolibc_enosys(__func__, old, new);
+	return my_syscall2(__NR_dup2, old, new);
 #endif
 }
 
@@ -327,10 +334,8 @@ pid_t sys_fork(void)
 	 * will not use the rest with no other flag.
 	 */
 	return my_syscall5(__NR_clone, SIGCHLD, 0, 0, 0, 0);
-#elif defined(__NR_fork)
-	return my_syscall0(__NR_fork);
 #else
-	return __nolibc_enosys(__func__);
+	return my_syscall0(__NR_fork);
 #endif
 }
 #endif
@@ -347,7 +352,7 @@ pid_t sys_vfork(void)
 {
 #if defined(__NR_vfork)
 	return my_syscall0(__NR_vfork);
-#elif defined(__NR_clone3)
+#else
 	/*
 	 * clone() could be used but has different argument orders per
 	 * architecture.
@@ -358,8 +363,6 @@ pid_t sys_vfork(void)
 	};
 
 	return my_syscall2(__NR_clone3, &args, sizeof(args));
-#else
-	return __nolibc_enosys(__func__);
 #endif
 }
 #endif
@@ -569,10 +572,8 @@ int sys_link(const char *old, const char *new)
 {
 #if defined(__NR_linkat)
 	return my_syscall5(__NR_linkat, AT_FDCWD, old, AT_FDCWD, new, 0);
-#elif defined(__NR_link)
-	return my_syscall2(__NR_link, old, new);
 #else
-	return __nolibc_enosys(__func__, old, new);
+	return my_syscall2(__NR_link, old, new);
 #endif
 }
 
@@ -593,41 +594,27 @@ off_t sys_lseek(int fd, off_t offset, int whence)
 #if defined(__NR_lseek)
 	return my_syscall3(__NR_lseek, fd, offset, whence);
 #else
-	return __nolibc_enosys(__func__, fd, offset, whence);
-#endif
-}
+	__kernel_loff_t loff = 0;
+	off_t result;
+	int ret;
 
-static __attribute__((unused))
-int sys_llseek(int fd, unsigned long offset_high, unsigned long offset_low,
-	       __kernel_loff_t *result, int whence)
-{
-#if defined(__NR_llseek)
-	return my_syscall5(__NR_llseek, fd, offset_high, offset_low, result, whence);
-#else
-	return __nolibc_enosys(__func__, fd, offset_high, offset_low, result, whence);
+	/* Only exists on 32bit where nolibc off_t is also 32bit */
+	ret = my_syscall5(__NR_llseek, fd, 0, offset, &loff, whence);
+	if (ret < 0)
+		result = ret;
+	else if (loff != (off_t)loff)
+		result = -EOVERFLOW;
+	else
+		result = loff;
+
+	return result;
 #endif
 }
 
 static __attribute__((unused))
 off_t lseek(int fd, off_t offset, int whence)
 {
-	__kernel_loff_t loff = 0;
-	off_t result;
-	int ret;
-
-	result = sys_lseek(fd, offset, whence);
-	if (result == -ENOSYS) {
-		/* Only exists on 32bit where nolibc off_t is also 32bit */
-		ret = sys_llseek(fd, 0, offset, &loff, whence);
-		if (ret < 0)
-			result = ret;
-		else if (loff != (off_t)loff)
-			result = -EOVERFLOW;
-		else
-			result = loff;
-	}
-
-	return __sysret(result);
+	return __sysret(sys_lseek(fd, offset, whence));
 }
 
 
@@ -640,10 +627,8 @@ int sys_mkdir(const char *path, mode_t mode)
 {
 #if defined(__NR_mkdirat)
 	return my_syscall3(__NR_mkdirat, AT_FDCWD, path, mode);
-#elif defined(__NR_mkdir)
-	return my_syscall2(__NR_mkdir, path, mode);
 #else
-	return __nolibc_enosys(__func__, path, mode);
+	return my_syscall2(__NR_mkdir, path, mode);
 #endif
 }
 
@@ -662,10 +647,8 @@ int sys_rmdir(const char *path)
 {
 #if defined(__NR_rmdir)
 	return my_syscall1(__NR_rmdir, path);
-#elif defined(__NR_unlinkat)
-	return my_syscall3(__NR_unlinkat, AT_FDCWD, path, AT_REMOVEDIR);
 #else
-	return __nolibc_enosys(__func__, path);
+	return my_syscall3(__NR_unlinkat, AT_FDCWD, path, AT_REMOVEDIR);
 #endif
 }
 
@@ -685,10 +668,8 @@ long sys_mknod(const char *path, mode_t mode, dev_t dev)
 {
 #if defined(__NR_mknodat)
 	return my_syscall4(__NR_mknodat, AT_FDCWD, path, mode, dev);
-#elif defined(__NR_mknod)
-	return my_syscall3(__NR_mknod, path, mode, dev);
 #else
-	return __nolibc_enosys(__func__, path, mode, dev);
+	return my_syscall3(__NR_mknod, path, mode, dev);
 #endif
 }
 
@@ -801,7 +782,7 @@ int sys_select(int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeva
 		t.tv_nsec = timeout->tv_usec * 1000;
 	}
 	return my_syscall6(__NR_pselect6, nfds, rfds, wfds, efds, timeout ? &t : NULL, NULL);
-#elif defined(__NR_pselect6_time64)
+#else
 	struct __kernel_timespec t;
 
 	if (timeout) {
@@ -809,8 +790,6 @@ int sys_select(int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeva
 		t.tv_nsec = timeout->tv_usec * 1000;
 	}
 	return my_syscall6(__NR_pselect6_time64, nfds, rfds, wfds, efds, timeout ? &t : NULL, NULL);
-#else
-	return __nolibc_enosys(__func__, nfds, rfds, wfds, efds, timeout);
 #endif
 }
 
@@ -874,10 +853,8 @@ int sys_symlink(const char *old, const char *new)
 {
 #if defined(__NR_symlinkat)
 	return my_syscall3(__NR_symlinkat, old, AT_FDCWD, new);
-#elif defined(__NR_symlink)
-	return my_syscall2(__NR_symlink, old, new);
 #else
-	return __nolibc_enosys(__func__, old, new);
+	return my_syscall2(__NR_symlink, old, new);
 #endif
 }
 
@@ -931,10 +908,8 @@ int sys_unlink(const char *path)
 {
 #if defined(__NR_unlinkat)
 	return my_syscall3(__NR_unlinkat, AT_FDCWD, path, 0);
-#elif defined(__NR_unlink)
-	return my_syscall1(__NR_unlink, path);
 #else
-	return __nolibc_enosys(__func__, path);
+	return my_syscall1(__NR_unlink, path);
 #endif
 }
 
diff --git a/tools/include/nolibc/sys/random.h b/tools/include/nolibc/sys/random.h
index 8d9749f..cd5d25c 100644
--- a/tools/include/nolibc/sys/random.h
+++ b/tools/include/nolibc/sys/random.h
@@ -22,13 +22,13 @@
 static __attribute__((unused))
 ssize_t sys_getrandom(void *buf, size_t buflen, unsigned int flags)
 {
-       return my_syscall3(__NR_getrandom, buf, buflen, flags);
+	return my_syscall3(__NR_getrandom, buf, buflen, flags);
 }
 
 static __attribute__((unused))
 ssize_t getrandom(void *buf, size_t buflen, unsigned int flags)
 {
-       return __sysret(sys_getrandom(buf, buflen, flags));
+	return __sysret(sys_getrandom(buf, buflen, flags));
 }
 
 #endif /* _NOLIBC_SYS_RANDOM_H */
diff --git a/tools/include/nolibc/sys/timerfd.h b/tools/include/nolibc/sys/timerfd.h
index 4375d54..5dd6103 100644
--- a/tools/include/nolibc/sys/timerfd.h
+++ b/tools/include/nolibc/sys/timerfd.h
@@ -34,7 +34,7 @@ int sys_timerfd_gettime(int fd, struct itimerspec *curr_value)
 {
 #if defined(__NR_timerfd_gettime)
 	return my_syscall2(__NR_timerfd_gettime, fd, curr_value);
-#elif defined(__NR_timerfd_gettime64)
+#else
 	struct __kernel_itimerspec kcurr_value;
 	int ret;
 
@@ -42,8 +42,6 @@ int sys_timerfd_gettime(int fd, struct itimerspec *curr_value)
 	__nolibc_timespec_kernel_to_user(&kcurr_value.it_interval, &curr_value->it_interval);
 	__nolibc_timespec_kernel_to_user(&kcurr_value.it_value, &curr_value->it_value);
 	return ret;
-#else
-	return __nolibc_enosys(__func__, fd, curr_value);
 #endif
 }
 
@@ -60,7 +58,7 @@ int sys_timerfd_settime(int fd, int flags,
 {
 #if defined(__NR_timerfd_settime)
 	return my_syscall4(__NR_timerfd_settime, fd, flags, new_value, old_value);
-#elif defined(__NR_timerfd_settime64)
+#else
 	struct __kernel_itimerspec knew_value, kold_value;
 	int ret;
 
@@ -72,8 +70,6 @@ int sys_timerfd_settime(int fd, int flags,
 		__nolibc_timespec_kernel_to_user(&kold_value.it_value, &old_value->it_value);
 	}
 	return ret;
-#else
-	return __nolibc_enosys(__func__, fd, flags, new_value, old_value);
 #endif
 }
 
diff --git a/tools/include/nolibc/sys/wait.h b/tools/include/nolibc/sys/wait.h
index 56ddb80..4e66e1f 100644
--- a/tools/include/nolibc/sys/wait.h
+++ b/tools/include/nolibc/sys/wait.h
@@ -16,28 +16,11 @@
 
 /*
  * pid_t wait(int *status);
- * pid_t wait4(pid_t pid, int *status, int options, struct rusage *rusage);
  * pid_t waitpid(pid_t pid, int *status, int options);
  * int waitid(idtype_t idtype, id_t id, siginfo_t *infop, int options);
  */
 
 static __attribute__((unused))
-pid_t sys_wait4(pid_t pid, int *status, int options, struct rusage *rusage)
-{
-#ifdef __NR_wait4
-	return my_syscall4(__NR_wait4, pid, status, options, rusage);
-#else
-	return __nolibc_enosys(__func__, pid, status, options, rusage);
-#endif
-}
-
-static __attribute__((unused))
-pid_t wait4(pid_t pid, int *status, int options, struct rusage *rusage)
-{
-	return __sysret(sys_wait4(pid, status, options, rusage));
-}
-
-static __attribute__((unused))
 int sys_waitid(int which, pid_t pid, siginfo_t *infop, int options, struct rusage *rusage)
 {
 	return my_syscall5(__NR_waitid, which, pid, infop, options, rusage);
diff --git a/tools/include/nolibc/time.h b/tools/include/nolibc/time.h
index d02bc44..6c276b8 100644
--- a/tools/include/nolibc/time.h
+++ b/tools/include/nolibc/time.h
@@ -45,7 +45,7 @@ int sys_clock_getres(clockid_t clockid, struct timespec *res)
 {
 #if defined(__NR_clock_getres)
 	return my_syscall2(__NR_clock_getres, clockid, res);
-#elif defined(__NR_clock_getres_time64)
+#else
 	struct __kernel_timespec kres;
 	int ret;
 
@@ -53,8 +53,6 @@ int sys_clock_getres(clockid_t clockid, struct timespec *res)
 	if (res)
 		__nolibc_timespec_kernel_to_user(&kres, res);
 	return ret;
-#else
-	return __nolibc_enosys(__func__, clockid, res);
 #endif
 }
 
@@ -69,7 +67,7 @@ int sys_clock_gettime(clockid_t clockid, struct timespec *tp)
 {
 #if defined(__NR_clock_gettime)
 	return my_syscall2(__NR_clock_gettime, clockid, tp);
-#elif defined(__NR_clock_gettime64)
+#else
 	struct __kernel_timespec ktp;
 	int ret;
 
@@ -77,8 +75,6 @@ int sys_clock_gettime(clockid_t clockid, struct timespec *tp)
 	if (tp)
 		__nolibc_timespec_kernel_to_user(&ktp, tp);
 	return ret;
-#else
-	return __nolibc_enosys(__func__, clockid, tp);
 #endif
 }
 
@@ -133,7 +129,8 @@ static __attribute__((unused))
 int clock_nanosleep(clockid_t clockid, int flags, const struct timespec *rqtp,
 		    struct timespec *rmtp)
 {
-	return __sysret(sys_clock_nanosleep(clockid, flags, rqtp, rmtp));
+	/* Directly return a positive error number */
+	return -sys_clock_nanosleep(clockid, flags, rqtp, rmtp);
 }
 
 static __inline__
@@ -145,7 +142,7 @@ double difftime(time_t time1, time_t time2)
 static __inline__
 int nanosleep(const struct timespec *rqtp, struct timespec *rmtp)
 {
-	return clock_nanosleep(CLOCK_REALTIME, 0, rqtp, rmtp);
+	return __sysret(sys_clock_nanosleep(CLOCK_REALTIME, 0, rqtp, rmtp));
 }
 
 
diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
index 25bfc77..7405fa2 100644
--- a/tools/include/nolibc/unistd.h
+++ b/tools/include/nolibc/unistd.h
@@ -33,7 +33,7 @@
 static __attribute__((unused))
 int sys_faccessat(int fd, const char *path, int amode, int flag)
 {
-       return my_syscall4(__NR_faccessat, fd, path, amode, flag);
+	return my_syscall4(__NR_faccessat, fd, path, amode, flag);
 }
 
 static __attribute__((unused))
diff --git a/tools/testing/selftests/arm64/abi/tpidr2.c b/tools/testing/selftests/arm64/abi/tpidr2.c
index 4c89ab0..1703543 100644
--- a/tools/testing/selftests/arm64/abi/tpidr2.c
+++ b/tools/testing/selftests/arm64/abi/tpidr2.c
@@ -182,16 +182,16 @@ static int write_clone_read(void)
 	}
 
 	for (;;) {
-		waiting = wait4(ret, &status, __WCLONE, NULL);
+		waiting = waitpid(ret, &status, __WCLONE);
 
 		if (waiting < 0) {
 			if (errno == EINTR)
 				continue;
-			ksft_print_msg("wait4() failed: %d\n", errno);
+			ksft_print_msg("waitpid() failed: %d\n", errno);
 			return 0;
 		}
 		if (waiting != ret) {
-			ksft_print_msg("wait4() returned wrong PID %d\n",
+			ksft_print_msg("waitpid() returned wrong PID %d\n",
 				       waiting);
 			return 0;
 		}
diff --git a/tools/testing/selftests/nolibc/Makefile.nolibc b/tools/testing/selftests/nolibc/Makefile.nolibc
index 0fb759b..330e000 100644
--- a/tools/testing/selftests/nolibc/Makefile.nolibc
+++ b/tools/testing/selftests/nolibc/Makefile.nolibc
@@ -262,19 +262,22 @@ REPORT  ?= awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{if (!f) printf("\n"); f++
 		if (f || !p || !done) printf("failure\n"); else if (s) printf("warning\n"); else printf("success\n");; \
 		printf("\nSee all results in %s\n", ARGV[1]); }'
 
+# Execute the toplevel kernel Makefile
+KBUILD_MAKE = $(MAKE) -C $(srctree) ARCH=$(ARCH) CROSS_COMPILE=$(CROSS_COMPILE) LLVM=
+
 help:
 	@echo "Supported targets under selftests/nolibc:"
 	@echo "  all               call the \"run\" target below"
 	@echo "  help              this help"
 	@echo "  sysroot           create the nolibc sysroot here (uses \$$ARCH)"
-	@echo "  nolibc-test       build the executable (uses \$$CC and \$$CROSS_COMPILE)"
+	@echo "  nolibc-test       build the executable (uses \$$CC or \$$CROSS_COMPILE)"
 	@echo "  libc-test         build an executable using the compiler's default libc instead"
 	@echo "  run-user          runs the executable under QEMU (uses \$$XARCH, \$$TEST)"
 	@echo "  initramfs.cpio    prepare the initramfs archive with nolibc-test"
 	@echo "  initramfs         prepare the initramfs tree with nolibc-test"
 	@echo "  defconfig         create a fresh new default config (uses \$$XARCH)"
-	@echo "  kernel            (re)build the kernel (uses \$$XARCH)"
-	@echo "  kernel-standalone (re)build the kernel with the initramfs (uses \$$XARCH)"
+	@echo "  kernel            (re)build the kernel (uses \$$XARCH, \$$CROSS_COMPILE)"
+	@echo "  kernel-standalone (re)build the kernel with the initramfs (uses \$$XARCH, \$$CROSS_COMPILE)"
 	@echo "  run               runs the kernel in QEMU after building it (uses \$$XARCH, \$$TEST)"
 	@echo "  rerun             runs a previously prebuilt kernel in QEMU (uses \$$XARCH, \$$TEST)"
 	@echo "  clean             clean the sysroot, initramfs, build and output files"
@@ -340,17 +343,17 @@ initramfs: nolibc-test
 	$(Q)cp nolibc-test initramfs/init
 
 defconfig:
-	$(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(DEFCONFIG)
+	$(Q)$(KBUILD_MAKE) $(DEFCONFIG)
 	$(Q)if [ -n "$(EXTRACONFIG)" ]; then \
 		$(srctree)/scripts/config --file $(objtree)/.config $(EXTRACONFIG); \
-		$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) olddefconfig < /dev/null; \
+		$(KBUILD_MAKE) olddefconfig < /dev/null; \
 	fi
 
 kernel:
-	$(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) < /dev/null
+	$(Q)$(KBUILD_MAKE) $(IMAGE_NAME) < /dev/null
 
 kernel-standalone: initramfs
-	$(Q)$(MAKE) -C $(srctree) ARCH=$(ARCH) CC=$(CC) CROSS_COMPILE=$(CROSS_COMPILE) $(IMAGE_NAME) CONFIG_INITRAMFS_SOURCE=$(CURDIR)/initramfs < /dev/null
+	$(Q)$(KBUILD_MAKE) $(IMAGE_NAME) CONFIG_INITRAMFS_SOURCE=$(CURDIR)/initramfs < /dev/null
 
 # run the tests after building the kernel
 run: kernel initramfs.cpio
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index a297ee0..29de215 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -196,8 +196,8 @@ int expect_zr(int expr, int llen)
 }
 
 
-#define EXPECT_NZ(cond, expr, val)			\
-	do { if (!(cond)) result(llen, SKIPPED); else ret += expect_nz(expr, llen; } while (0)
+#define EXPECT_NZ(cond, expr)				\
+	do { if (!(cond)) result(llen, SKIPPED); else ret += expect_nz(expr, llen); } while (0)
 
 static __attribute__((unused))
 int expect_nz(int expr, int llen)
@@ -686,7 +686,6 @@ int expect_strtox(int llen, void *func, const char *input, int base, intmax_t ex
 #define CASE_TEST(name) \
 	case __LINE__: llen += printf("%d %s", test, #name);
 
-/* constructors validate that they are executed in definition order */
 __attribute__((constructor))
 static void constructor1(void)
 {
@@ -1334,6 +1333,7 @@ int run_syscall(int min, int max)
 		CASE_TEST(chroot_root);       EXPECT_SYSZR(euid0, chroot("/")); break;
 		CASE_TEST(chroot_blah);       EXPECT_SYSER(1, chroot("/proc/self/blah"), -1, ENOENT); break;
 		CASE_TEST(chroot_exe);        EXPECT_SYSER(1, chroot(argv0), -1, ENOTDIR); break;
+		CASE_TEST(clock_nanosleep);   ts.tv_nsec = -1; EXPECT_EQ(1, EINVAL, clock_nanosleep(CLOCK_REALTIME, 0, &ts, NULL)); break;
 		CASE_TEST(close_m1);          EXPECT_SYSER(1, close(-1), -1, EBADF); break;
 		CASE_TEST(close_dup);         EXPECT_SYSZR(1, close(dup(0))); break;
 		CASE_TEST(dup_0);             tmp = dup(0);  EXPECT_SYSNE(1, tmp, -1); close(tmp); break;