Clean up compilation

Instead of mixing standard headers and internal redefinitions of standard
types, completely rely on the compiler for what is guaranteed for a free
standing environment. This results in the removal of kern/stddef.h and
kern/stdint.h. The kern/types.h header is reintroduced for the different
(and saner) purpose of defining types not specified in standard C,
namely ssize_t for now.

62 files changed, 183 insertions, 135 deletions

diff --git a/Makefile.am b/Makefile.am
index 33529765..649bc51d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,23 +1,41 @@
 EXTRA_DIST =
 MOSTLYCLEANFILES =
+AM_CPPFLAGS =
+AM_CFLAGS =
 
-AM_CPPFLAGS = \
-	-pipe \
-	-std=gnu99 \
-	-imacros config.h \
+AM_CPPFLAGS += -pipe
+AM_CPPFLAGS += -imacros config.h
+
+# Do not include headers from the hosted environment, but
+# do include headers from the compiler.
+AM_CPPFLAGS += -nostdinc
+AM_CPPFLAGS += -isystem $(shell $(CC) -print-file-name=include)
+
+AM_CPPFLAGS += \
 	-I$(top_srcdir) \
+	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/arch/$(arch)
 
-AM_CFLAGS = \
+AM_CFLAGS += -ffreestanding
+
+# TODO Adopt C11
+AM_CFLAGS += -std=gnu99
+
+AM_CFLAGS += \
 	-Wall \
 	-Wextra \
 	-Wshadow \
 	-Wmissing-prototypes \
-	-Wstrict-prototypes \
+	-Wstrict-prototypes
+
+AM_CFLAGS += \
 	-fsigned-char \
-	-ffreestanding \
-	-fno-common \
-	-fno-stack-protector
+	-fno-common
+
+# TODO Add stack protector support
+AM_CFLAGS += -fno-stack-protector
+
+AM_CFLAGS += -nostdlib
 
 SUFFIXES = .lds .lds.S
 
diff --git a/Makefrag.am b/Makefrag.am
index fca8820a..01e7f5b0 100644
--- a/Makefrag.am
+++ b/Makefrag.am
@@ -1,5 +1,8 @@
 include arch/x86/Makefrag.am
 
+x15_SOURCES += \
+	include/string.h
+
 x15_SOURCES +=              \
 	kern/assert.h       \
 	kern/bitmap.c       \
@@ -54,8 +57,6 @@ x15_SOURCES +=              \
 	kern/sref.c         \
 	kern/sref.h         \
 	kern/sref_i.h       \
-	kern/stddef.h       \
-	kern/stdint.h       \
 	kern/string.c       \
 	kern/string.h       \
 	kern/task.c         \
@@ -63,6 +64,7 @@ x15_SOURCES +=              \
 	kern/thread.c       \
 	kern/thread.h       \
 	kern/thread_i.h     \
+	kern/types.h        \
 	kern/work.c         \
 	kern/work.h         \
 	kern/xcall.c        \
diff --git a/arch/x86/machine/acpimp.c b/arch/x86/machine/acpimp.c
index ef93bc43..2c3dc6c2 100644
--- a/arch/x86/machine/acpimp.c
+++ b/arch/x86/machine/acpimp.c
@@ -15,15 +15,16 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
 #include <kern/assert.h>
 #include <kern/init.h>
 #include <kern/kmem.h>
 #include <kern/macros.h>
 #include <kern/panic.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <machine/acpimp.h>
 #include <machine/biosmem.h>
 #include <machine/cpu.h>
diff --git a/arch/x86/machine/atomic.h b/arch/x86/machine/atomic.h
index c990526c..b56da522 100644
--- a/arch/x86/machine/atomic.h
+++ b/arch/x86/machine/atomic.h
@@ -23,7 +23,7 @@
 #ifndef _X86_ATOMIC_H
 #define _X86_ATOMIC_H
 
-#include <kern/stdint.h>
+#include <stdint.h>
 
 #define ATOMIC_ADD(ptr, delta)      \
     asm volatile("lock add %1, %0"  \
diff --git a/arch/x86/machine/biosmem.c b/arch/x86/machine/biosmem.c
index 6e6410cf..4208b72b 100644
--- a/arch/x86/machine/biosmem.c
+++ b/arch/x86/machine/biosmem.c
@@ -16,6 +16,9 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
 
 #include <kern/assert.h>
 #include <kern/init.h>
@@ -23,9 +26,6 @@
 #include <kern/panic.h>
 #include <kern/param.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <machine/biosmem.h>
 #include <machine/boot.h>
 #include <machine/cpu.h>
diff --git a/arch/x86/machine/boot.c b/arch/x86/machine/boot.c
index a3fd3146..2ab1c6d5 100644
--- a/arch/x86/machine/boot.c
+++ b/arch/x86/machine/boot.c
@@ -43,6 +43,9 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
 
 #include <kern/evcnt.h>
 #include <kern/init.h>
@@ -54,9 +57,6 @@
 #include <kern/percpu.h>
 #include <kern/printk.h>
 #include <kern/sref.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <machine/biosmem.h>
 #include <machine/boot.h>
diff --git a/arch/x86/machine/cga.c b/arch/x86/machine/cga.c
index 1ab23582..c926ec3d 100644
--- a/arch/x86/machine/cga.c
+++ b/arch/x86/machine/cga.c
@@ -15,11 +15,12 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stdint.h>
+#include <string.h>
+
 #include <kern/init.h>
 #include <kern/macros.h>
 #include <kern/param.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <machine/io.h>
 #include <machine/cga.h>
 #include <vm/vm_page.h>
diff --git a/arch/x86/machine/cga.h b/arch/x86/machine/cga.h
index 0486fd96..2dc12cf4 100644
--- a/arch/x86/machine/cga.h
+++ b/arch/x86/machine/cga.h
@@ -21,7 +21,7 @@
 #ifndef _X86_CGA_H
 #define _X86_CGA_H
 
-#include <kern/stdint.h>
+#include <stdint.h>
 
 /*
  * Initialize the cga module.
diff --git a/arch/x86/machine/cpu.c b/arch/x86/machine/cpu.c
index 5fc21315..19282121 100644
--- a/arch/x86/machine/cpu.c
+++ b/arch/x86/machine/cpu.c
@@ -15,6 +15,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
 #include <kern/assert.h>
 #include <kern/init.h>
 #include <kern/macros.h>
@@ -22,9 +26,6 @@
 #include <kern/param.h>
 #include <kern/percpu.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <kern/xcall.h>
 #include <machine/acpimp.h>
diff --git a/arch/x86/machine/cpu.h b/arch/x86/machine/cpu.h
index a18712c8..862799e8 100644
--- a/arch/x86/machine/cpu.h
+++ b/arch/x86/machine/cpu.h
@@ -95,9 +95,10 @@
 
 #ifndef __ASSEMBLER__
 
+#include <stdint.h>
+
 #include <kern/macros.h>
 #include <kern/percpu.h>
-#include <kern/stdint.h>
 #include <machine/lapic.h>
 #include <machine/pit.h>
 
diff --git a/arch/x86/machine/io.h b/arch/x86/machine/io.h
index 6b10f0eb..fb566b95 100644
--- a/arch/x86/machine/io.h
+++ b/arch/x86/machine/io.h
@@ -18,7 +18,7 @@
 #ifndef _X86_IO_H
 #define _X86_IO_H
 
-#include <kern/stdint.h>
+#include <stdint.h>
 
 /*
  * Read a byte from an I/O port.
diff --git a/arch/x86/machine/lapic.c b/arch/x86/machine/lapic.c
index 26b0dd50..c0d10e5c 100644
--- a/arch/x86/machine/lapic.c
+++ b/arch/x86/machine/lapic.c
@@ -15,13 +15,14 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/init.h>
 #include <kern/macros.h>
 #include <kern/panic.h>
 #include <kern/param.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 #include <kern/thread.h>
 #include <machine/cpu.h>
 #include <machine/lapic.h>
diff --git a/arch/x86/machine/lapic.h b/arch/x86/machine/lapic.h
index 8c87adc6..802d1251 100644
--- a/arch/x86/machine/lapic.h
+++ b/arch/x86/machine/lapic.h
@@ -18,7 +18,8 @@
 #ifndef _X86_LAPIC_H
 #define _X86_LAPIC_H
 
-#include <kern/stdint.h>
+#include <stdint.h>
+
 #include <machine/trap.h>
 
 /*
diff --git a/arch/x86/machine/multiboot.h b/arch/x86/machine/multiboot.h
index 4a0502c8..02c8a330 100644
--- a/arch/x86/machine/multiboot.h
+++ b/arch/x86/machine/multiboot.h
@@ -46,8 +46,9 @@
 
 #ifndef __ASSEMBLER__
 
+#include <stdint.h>
+
 #include <kern/macros.h>
-#include <kern/stdint.h>
 
 /*
  * A multiboot module.
diff --git a/arch/x86/machine/pic.c b/arch/x86/machine/pic.c
index 440ca3a7..db26a166 100644
--- a/arch/x86/machine/pic.c
+++ b/arch/x86/machine/pic.c
@@ -15,10 +15,11 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/init.h>
 #include <kern/panic.h>
-#include <kern/stdint.h>
 #include <machine/io.h>
 #include <machine/cpu.h>
 #include <machine/pic.h>
diff --git a/arch/x86/machine/pmap.c b/arch/x86/machine/pmap.c
index ea49856e..7cf50866 100644
--- a/arch/x86/machine/pmap.c
+++ b/arch/x86/machine/pmap.c
@@ -18,6 +18,9 @@
  * TODO Review locking.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/assert.h>
 #include <kern/condition.h>
 #include <kern/cpumap.h>
@@ -33,8 +36,6 @@
 #include <kern/percpu.h>
 #include <kern/spinlock.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <machine/biosmem.h>
 #include <machine/boot.h>
diff --git a/arch/x86/machine/pmap.h b/arch/x86/machine/pmap.h
index 1806a6fb..4fdda23f 100644
--- a/arch/x86/machine/pmap.h
+++ b/arch/x86/machine/pmap.h
@@ -96,10 +96,11 @@
 
 #ifndef __ASSEMBLER__
 
+#include <stdint.h>
+
 #include <kern/cpumap.h>
 #include <kern/list.h>
 #include <kern/mutex.h>
-#include <kern/stdint.h>
 #include <kern/thread.h>
 #include <machine/cpu.h>
 #include <machine/trap.h>
diff --git a/arch/x86/machine/strace.c b/arch/x86/machine/strace.c
index e65efb08..e40b3645 100644
--- a/arch/x86/machine/strace.c
+++ b/arch/x86/machine/strace.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/init.h>
 #include <kern/kmem.h>
 #include <kern/param.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <machine/elf.h>
 #include <machine/multiboot.h>
 #include <machine/pmap.h>
diff --git a/arch/x86/machine/string.c b/arch/x86/machine/string.c
index 26ce941b..cdf00e3f 100644
--- a/arch/x86/machine/string.c
+++ b/arch/x86/machine/string.c
@@ -15,9 +15,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/param.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 
 #ifdef ARCH_STRING_MEMCPY
 void *
diff --git a/kern/stdint.h b/include/string.h
index 9c6cab0e..0eee8969 100644
--- a/kern/stdint.h
+++ b/include/string.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010-2017 Richard Braun.
+ * Copyright (c) 2017 Richard Braun.
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -15,19 +15,9 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef _KERN_STDINT_H
-#define _KERN_STDINT_H
+#ifndef _STRING_H
+#define _STRING_H
 
-typedef long intptr_t;
-typedef unsigned long uintptr_t;
+#include <kern/string.h>
 
-typedef signed char int8_t;
-typedef unsigned char uint8_t;
-typedef signed short int16_t;
-typedef unsigned short uint16_t;
-typedef signed int int32_t;
-typedef unsigned int uint32_t;
-typedef signed long long int64_t;
-typedef unsigned long long uint64_t;
-
-#endif /* _KERN_STDINT_H */
+#endif /* _STRING_H */
diff --git a/kern/bitmap.c b/kern/bitmap.c
index b3117dfb..d270b9f5 100644
--- a/kern/bitmap.c
+++ b/kern/bitmap.c
@@ -15,10 +15,11 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <string.h>
+
 #include <kern/bitmap.h>
 #include <kern/bitmap_i.h>
 #include <kern/limits.h>
-#include <kern/string.h>
 
 int
 bitmap_cmp(const unsigned long *a, const unsigned long *b, int nr_bits)
diff --git a/kern/bitmap.h b/kern/bitmap.h
index 6489b486..77dfac1b 100644
--- a/kern/bitmap.h
+++ b/kern/bitmap.h
@@ -24,9 +24,10 @@
 #ifndef _KERN_BITMAP_H
 #define _KERN_BITMAP_H
 
+#include <string.h>
+
 #include <kern/bitmap_i.h>
 #include <kern/limits.h>
-#include <kern/string.h>
 #include <machine/atomic.h>
 
 #define BITMAP_DECLARE(name, nr_bits) unsigned long name[BITMAP_LONGS(nr_bits)]
diff --git a/kern/condition.c b/kern/condition.c
index 7d83f47d..467cb85a 100644
--- a/kern/condition.c
+++ b/kern/condition.c
@@ -22,13 +22,14 @@
  * locked, the current owner does the same when unlocking.
  */
 
+#include <stddef.h>
+
 #include <kern/assert.h>
 #include <kern/condition.h>
 #include <kern/list.h>
 #include <kern/mutex.h>
 #include <kern/mutex_i.h>
 #include <kern/spinlock.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 
 void
diff --git a/kern/condition.h b/kern/condition.h
index 4e7f7f0f..a61c2a9d 100644
--- a/kern/condition.h
+++ b/kern/condition.h
@@ -21,10 +21,11 @@
 #ifndef _KERN_CONDITION_H
 #define _KERN_CONDITION_H
 
+#include <stddef.h>
+
 #include <kern/condition_types.h>
 #include <kern/list.h>
 #include <kern/spinlock.h>
-#include <kern/stddef.h>
 
 static inline void
 condition_init(struct condition *condition)
diff --git a/kern/cpumap.c b/kern/cpumap.c
index 2cc3511c..5582e681 100644
--- a/kern/cpumap.c
+++ b/kern/cpumap.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+
 #include <kern/bitmap.h>
 #include <kern/cpumap.h>
 #include <kern/error.h>
 #include <kern/kmem.h>
 #include <kern/param.h>
-#include <kern/stddef.h>
 #include <machine/cpu.h>
 
 static struct cpumap cpumap_active_cpus __read_mostly = { { 1 } };
diff --git a/kern/evcnt.c b/kern/evcnt.c
index 803516d0..e993edd9 100644
--- a/kern/evcnt.c
+++ b/kern/evcnt.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <string.h>
+
 #include <kern/evcnt.h>
 #include <kern/init.h>
 #include <kern/list.h>
 #include <kern/mutex.h>
 #include <kern/printk.h>
-#include <kern/string.h>
 
 /*
  * Global list of all registered counters.
diff --git a/kern/kmem.c b/kern/kmem.c
index 49ec177b..e406115b 100644
--- a/kern/kmem.c
+++ b/kern/kmem.c
@@ -42,6 +42,9 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
 
 #include <kern/assert.h>
 #include <kern/init.h>
@@ -56,9 +59,6 @@
 #include <kern/param.h>
 #include <kern/printk.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <machine/cpu.h>
 #include <machine/pmap.h>
diff --git a/kern/kmem.h b/kern/kmem.h
index b1861557..8f6c773c 100644
--- a/kern/kmem.h
+++ b/kern/kmem.h
@@ -21,7 +21,7 @@
 #ifndef _KERN_KMEM_H
 #define _KERN_KMEM_H
 
-#include <kern/stddef.h>
+#include <stddef.h>
 
 /*
  * Object cache.
diff --git a/kern/kmem_i.h b/kern/kmem_i.h
index 08b11c54..b9972d78 100644
--- a/kern/kmem_i.h
+++ b/kern/kmem_i.h
@@ -18,10 +18,11 @@
 #ifndef _KERN_KMEM_I_H
 #define _KERN_KMEM_I_H
 
+#include <stddef.h>
+
 #include <kern/list.h>
 #include <kern/mutex.h>
 #include <kern/param.h>
-#include <kern/stddef.h>
 
 /*
  * Per-processor cache of pre-constructed objects.
diff --git a/kern/list.h b/kern/list.h
index 8cd5a2d7..c31b71a7 100644
--- a/kern/list.h
+++ b/kern/list.h
@@ -22,11 +22,11 @@
 #define _KERN_LIST_H
 
 #include <stdbool.h>
+#include <stddef.h>
 
 #include <kern/list_types.h>
 #include <kern/llsync.h>
 #include <kern/macros.h>
-#include <kern/stddef.h>
 
 /*
  * Structure used as both head and node.
diff --git a/kern/llsync.c b/kern/llsync.c
index 6859f59e..059773f4 100644
--- a/kern/llsync.c
+++ b/kern/llsync.c
@@ -33,6 +33,7 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
 
 #include <kern/assert.h>
 #include <kern/condition.h>
@@ -49,7 +50,6 @@
 #include <kern/printk.h>
 #include <kern/spinlock.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
 #include <kern/work.h>
 #include <machine/cpu.h>
 
diff --git a/kern/macros.h b/kern/macros.h
index 068bb035..a5b7b032 100644
--- a/kern/macros.h
+++ b/kern/macros.h
@@ -22,7 +22,7 @@
 #define _KERN_MACROS_H
 
 #ifndef __ASSEMBLER__
-#include <kern/stddef.h>
+#include <stddef.h>
 #endif /* __ASSEMBLER__ */
 
 #define MACRO_BEGIN         ({
@@ -64,7 +64,11 @@
 
 #define __noreturn          __attribute__((noreturn))
 #define __aligned(x)        __attribute__((aligned(x)))
+
+#ifndef __always_inline
 #define __always_inline     inline __attribute__((always_inline))
+#endif /* __attribute__ */
+
 #define __section(x)        __attribute__((section(x)))
 #define __packed            __attribute__((packed))
 #define __alias(x)          __attribute__((alias(x)))
diff --git a/kern/percpu.c b/kern/percpu.c
index ab7b4fb6..b57788ed 100644
--- a/kern/percpu.c
+++ b/kern/percpu.c
@@ -15,6 +15,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
 #include <kern/assert.h>
 #include <kern/error.h>
 #include <kern/init.h>
@@ -23,9 +27,6 @@
 #include <kern/param.h>
 #include <kern/percpu.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <machine/cpu.h>
 #include <vm/vm_kmem.h>
 #include <vm/vm_page.h>
diff --git a/kern/percpu.h b/kern/percpu.h
index a9d1eb3b..456131a0 100644
--- a/kern/percpu.h
+++ b/kern/percpu.h
@@ -53,9 +53,10 @@
 #ifndef _KERN_PERCPU_H
 #define _KERN_PERCPU_H
 
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/macros.h>
-#include <kern/stdint.h>
 
 #define PERCPU_SECTION .percpu
 #define __percpu __section(QUOTE(PERCPU_SECTION))
diff --git a/kern/rbtree.c b/kern/rbtree.c
index 0d0a844c..e2ea54ad 100644
--- a/kern/rbtree.c
+++ b/kern/rbtree.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/macros.h>
 #include <kern/rbtree.h>
 #include <kern/rbtree_i.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 
 /*
  * Return the index of a node in the children array of its parent.
diff --git a/kern/rbtree.h b/kern/rbtree.h
index dd17e956..02a657c1 100644
--- a/kern/rbtree.h
+++ b/kern/rbtree.h
@@ -21,10 +21,11 @@
 #ifndef _KERN_RBTREE_H
 #define _KERN_RBTREE_H
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/macros.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 
 /*
  * Indexes of the left and right nodes in the children array of a node.
diff --git a/kern/rbtree_i.h b/kern/rbtree_i.h
index f788e830..99722977 100644
--- a/kern/rbtree_i.h
+++ b/kern/rbtree_i.h
@@ -18,10 +18,11 @@
 #ifndef _KERN_RBTREE_I_H
 #define _KERN_RBTREE_I_H
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/macros.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 
 /*
  * Red-black node structure.
diff --git a/kern/rdxtree.c b/kern/rdxtree.c
index 90676e04..788f3ba8 100644
--- a/kern/rdxtree.c
+++ b/kern/rdxtree.c
@@ -16,6 +16,9 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
 
 #include <kern/assert.h>
 #include <kern/error.h>
@@ -25,9 +28,6 @@
 #include <kern/macros.h>
 #include <kern/rdxtree.h>
 #include <kern/rdxtree_i.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <kern/work.h>
 
 /*
diff --git a/kern/rdxtree.h b/kern/rdxtree.h
index a0d19b55..e3a2ba06 100644
--- a/kern/rdxtree.h
+++ b/kern/rdxtree.h
@@ -26,8 +26,8 @@
 #ifndef _KERN_RDXTREE_H
 #define _KERN_RDXTREE_H
 
-#include <kern/stddef.h>
-#include <kern/stdint.h>
+#include <stddef.h>
+#include <stdint.h>
 
 typedef uint32_t rdxtree_key_t;
 
diff --git a/kern/sprintf.c b/kern/sprintf.c
index 386d9d3c..3d2bf2df 100644
--- a/kern/sprintf.c
+++ b/kern/sprintf.c
@@ -16,11 +16,12 @@
  */
 
 #include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
 
 #include <kern/limits.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
+#include <kern/types.h>
 
 /*
  * Formatting flags.
diff --git a/kern/sref.c b/kern/sref.c
index dc5f446e..e1368c30 100644
--- a/kern/sref.c
+++ b/kern/sref.c
@@ -42,6 +42,7 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
 
 #include <kern/assert.h>
 #include <kern/condition.h>
@@ -58,7 +59,6 @@
 #include <kern/sprintf.h>
 #include <kern/sref.h>
 #include <kern/sref_i.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <machine/cpu.h>
 
diff --git a/kern/sref_i.h b/kern/sref_i.h
index 1452bbc9..5b63857f 100644
--- a/kern/sref_i.h
+++ b/kern/sref_i.h
@@ -18,8 +18,9 @@
 #ifndef _KERN_SREF_I_H
 #define _KERN_SREF_I_H
 
+#include <stdint.h>
+
 #include <kern/spinlock.h>
-#include <kern/stdint.h>
 #include <kern/work.h>
 
 #define SREF_WEAKREF_DYING  ((uintptr_t)1)
diff --git a/kern/string.c b/kern/string.c
index 88d251f8..05218e01 100644
--- a/kern/string.c
+++ b/kern/string.c
@@ -18,8 +18,9 @@
  * Trivial, portable implementations.
  */
 
-#include <kern/stddef.h>
-#include <kern/string.h>
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/param.h>
 
 #ifndef ARCH_STRING_MEMCPY
diff --git a/kern/string.h b/kern/string.h
index 238d0e73..7ce4ab8f 100644
--- a/kern/string.h
+++ b/kern/string.h
@@ -18,7 +18,7 @@
 #ifndef _KERN_STRING_H
 #define _KERN_STRING_H
 
-#include <kern/stddef.h>
+#include <stddef.h>
 
 void * memcpy(void *dest, const void *src, size_t n);
 void * memmove(void *dest, const void *src, size_t n);
diff --git a/kern/task.c b/kern/task.c
index e5b34d16..e415cb65 100644
--- a/kern/task.c
+++ b/kern/task.c
@@ -15,14 +15,15 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/error.h>
 #include <kern/init.h>
 #include <kern/kmem.h>
 #include <kern/list.h>
 #include <kern/param.h>
 #include <kern/spinlock.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <kern/task.h>
 #include <kern/thread.h>
 #include <vm/vm_kmem.h>
diff --git a/kern/thread.c b/kern/thread.c
index 0cb5008b..180f780d 100644
--- a/kern/thread.c
+++ b/kern/thread.c
@@ -81,6 +81,9 @@
  * weights in a smoother way than a raw scaling).
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/assert.h>
 #include <kern/condition.h>
 #include <kern/cpumap.h>
@@ -98,8 +101,6 @@
 #include <kern/spinlock.h>
 #include <kern/sprintf.h>
 #include <kern/sref.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <kern/task.h>
 #include <kern/thread.h>
 #include <kern/work.h>
diff --git a/kern/stddef.h b/kern/types.h
index b07c9924..2eb1064d 100644
--- a/kern/stddef.h
+++ b/kern/types.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010, 2011 Richard Braun.
+ * Copyright (c) 2017 Richard Braun.
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -13,23 +13,14 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * Machine-independent definitions for non-standard C types.
  */
 
-#ifndef _KERN_STDDEF_H
-#define _KERN_STDDEF_H
-
-#define NULL ((void *)0)
-
-#define offsetof(type, member) __builtin_offsetof(type, member)
+#ifndef _KERN_TYPES_H
+#define _KERN_TYPES_H
 
-#ifdef __LP64__
-typedef unsigned long size_t;
 typedef long ssize_t;
-typedef long ptrdiff_t;
-#else /* __LP64__ */
-typedef unsigned int size_t;
-typedef int ssize_t;
-typedef int ptrdiff_t;
-#endif /* __LP64__ */
 
-#endif /* _KERN_STDDEF_H */
+#endif /* _KERN_TYPES_H */
diff --git a/kern/work.c b/kern/work.c
index d7a221fa..6c798fbb 100644
--- a/kern/work.c
+++ b/kern/work.c
@@ -15,6 +15,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+
 #include <kern/assert.h>
 #include <kern/bitmap.h>
 #include <kern/error.h>
@@ -28,7 +30,6 @@
 #include <kern/printk.h>
 #include <kern/spinlock.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <kern/work.h>
 #include <machine/cpu.h>
diff --git a/kern/xcall.c b/kern/xcall.c
index 398001d1..565cd20a 100644
--- a/kern/xcall.c
+++ b/kern/xcall.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <stddef.h>
+
 #include <kern/assert.h>
 #include <kern/macros.h>
 #include <kern/param.h>
 #include <kern/percpu.h>
 #include <kern/spinlock.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <kern/xcall.h>
 #include <machine/mb.h>
diff --git a/test/test_llsync_defer.c b/test/test_llsync_defer.c
index e4cca214..954ea390 100644
--- a/test/test_llsync_defer.c
+++ b/test/test_llsync_defer.c
@@ -28,6 +28,9 @@
  * Each thread regularly prints a string to report that it's making progress.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/condition.h>
 #include <kern/error.h>
 #include <kern/kmem.h>
@@ -37,8 +40,6 @@
 #include <kern/panic.h>
 #include <kern/param.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <kern/work.h>
 #include <test/test.h>
diff --git a/test/test_pmap_update_mp.c b/test/test_pmap_update_mp.c
index 21882bf2..5f40c8ce 100644
--- a/test/test_pmap_update_mp.c
+++ b/test/test_pmap_update_mp.c
@@ -24,6 +24,9 @@
  * tables of the current processor have been updated.
  */
 
+#include <stddef.h>
+#include <string.h>
+
 #include <kern/condition.h>
 #include <kern/cpumap.h>
 #include <kern/error.h>
@@ -31,8 +34,6 @@
 #include <kern/panic.h>
 #include <kern/param.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <test/test.h>
 #include <vm/vm_kmem.h>
diff --git a/test/test_sref_dirty_zeroes.c b/test/test_sref_dirty_zeroes.c
index 042fb681..7f17ceea 100644
--- a/test/test_sref_dirty_zeroes.c
+++ b/test/test_sref_dirty_zeroes.c
@@ -26,6 +26,8 @@
  * and panics if it is.
  */
 
+#include <stddef.h>
+
 #include <kern/condition.h>
 #include <kern/error.h>
 #include <kern/evcnt.h>
@@ -35,7 +37,6 @@
 #include <kern/panic.h>
 #include <kern/sprintf.h>
 #include <kern/sref.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <test/test.h>
 #include <vm/vm_kmem.h>
diff --git a/test/test_sref_noref.c b/test/test_sref_noref.c
index d9fe63b8..b74338dc 100644
--- a/test/test_sref_noref.c
+++ b/test/test_sref_noref.c
@@ -32,6 +32,8 @@
  * to occur.
  */
 
+#include <stddef.h>
+
 #include <kern/condition.h>
 #include <kern/error.h>
 #include <kern/evcnt.h>
@@ -41,7 +43,6 @@
 #include <kern/panic.h>
 #include <kern/sprintf.h>
 #include <kern/sref.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <test/test.h>
 #include <vm/vm_kmem.h>
diff --git a/test/test_sref_weakref.c b/test/test_sref_weakref.c
index f618a483..20e8e155 100644
--- a/test/test_sref_weakref.c
+++ b/test/test_sref_weakref.c
@@ -32,11 +32,12 @@
  * first thread reinitializes the weak reference.
  */
 
+#include <stddef.h>
+
 #include <kern/error.h>
 #include <kern/evcnt.h>
 #include <kern/macros.h>
 #include <kern/sref.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <test/test.h>
 #include <vm/vm_kmem.h>
diff --git a/test/test_vm_page_fill.c b/test/test_vm_page_fill.c
index 55a328b2..c334407d 100644
--- a/test/test_vm_page_fill.c
+++ b/test/test_vm_page_fill.c
@@ -22,11 +22,12 @@
  * in which case this test will catch the error.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/cpumap.h>
 #include <kern/error.h>
 #include <kern/list.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 #include <kern/thread.h>
 #include <machine/pmap.h>
 #include <test/test.h>
diff --git a/test/test_xcall.c b/test/test_xcall.c
index 2d496de1..ab4fa113 100644
--- a/test/test_xcall.c
+++ b/test/test_xcall.c
@@ -20,11 +20,12 @@
  * processor, and another on a remote processor.
  */
 
+#include <stddef.h>
+
 #include <kern/error.h>
 #include <kern/cpumap.h>
 #include <kern/panic.h>
 #include <kern/printk.h>
-#include <kern/stddef.h>
 #include <kern/thread.h>
 #include <kern/xcall.h>
 #include <test/test.h>
diff --git a/vm/vm_kmem.c b/vm/vm_kmem.c
index 9a767e08..8a7272cb 100644
--- a/vm/vm_kmem.c
+++ b/vm/vm_kmem.c
@@ -18,13 +18,14 @@
  * TODO Rework so that pmap update errors can be handled.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/cpumap.h>
 #include <kern/init.h>
 #include <kern/panic.h>
 #include <kern/param.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 #include <machine/pmap.h>
 #include <machine/types.h>
 #include <vm/vm_adv.h>
diff --git a/vm/vm_kmem.h b/vm/vm_kmem.h
index eafb4183..c4b5295c 100644
--- a/vm/vm_kmem.h
+++ b/vm/vm_kmem.h
@@ -18,7 +18,8 @@
 #ifndef _VM_VM_KMEM_H
 #define _VM_VM_KMEM_H
 
-#include <kern/stdint.h>
+#include <stdint.h>
+
 #include <machine/types.h>
 
 /*
diff --git a/vm/vm_map.c b/vm/vm_map.c
index 883936c5..9fcc4f0a 100644
--- a/vm/vm_map.c
+++ b/vm/vm_map.c
@@ -19,6 +19,9 @@
  * needed for kernel allocation.
  */
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/error.h>
 #include <kern/init.h>
@@ -30,8 +33,6 @@
 #include <kern/param.h>
 #include <kern/printk.h>
 #include <kern/rbtree.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 #include <machine/pmap.h>
 #include <vm/vm_adv.h>
 #include <vm/vm_inherit.h>
diff --git a/vm/vm_map.h b/vm/vm_map.h
index e4d47301..1e17bbb4 100644
--- a/vm/vm_map.h
+++ b/vm/vm_map.h
@@ -21,10 +21,11 @@
 #ifndef _VM_VM_MAP_H
 #define _VM_VM_MAP_H
 
+#include <stdint.h>
+
 #include <kern/list.h>
 #include <kern/mutex.h>
 #include <kern/rbtree.h>
-#include <kern/stdint.h>
 #include <machine/pmap.h>
 #include <vm/vm_adv.h>
 #include <vm/vm_inherit.h>
diff --git a/vm/vm_page.c b/vm/vm_page.c
index 487e4624..df20790c 100644
--- a/vm/vm_page.c
+++ b/vm/vm_page.c
@@ -30,6 +30,9 @@
  */
 
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
 
 #include <kern/assert.h>
 #include <kern/init.h>
@@ -40,9 +43,6 @@
 #include <kern/param.h>
 #include <kern/printk.h>
 #include <kern/sprintf.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
-#include <kern/string.h>
 #include <kern/thread.h>
 #include <machine/cpu.h>
 #include <machine/pmap.h>
diff --git a/vm/vm_page.h b/vm/vm_page.h
index cd4dab10..139f1bff 100644
--- a/vm/vm_page.h
+++ b/vm/vm_page.h
@@ -21,13 +21,14 @@
 #ifndef _VM_VM_PAGE_H
 #define _VM_VM_PAGE_H
 
+#include <stddef.h>
+#include <stdint.h>
+
 #include <kern/assert.h>
 #include <kern/list.h>
 #include <kern/log2.h>
 #include <kern/macros.h>
 #include <kern/param.h>
-#include <kern/stddef.h>
-#include <kern/stdint.h>
 #include <machine/pmap.h>
 #include <machine/types.h>