diff --git a/include/pthread.h b/include/pthread.h
--- a/include/pthread.h
+++ b/include/pthread.h
@@ -43,7 +43,7 @@
 #include <sys/cdefs.h>
 #include <sys/_pthreadtypes.h>
 #include <machine/_limits.h>
-#include <machine/_types.h>
+#include <sys/_types.h>
 #include <sys/_sigset.h>
 #include <sched.h>
 #include <time.h>
diff --git a/sys/arm/include/_types.h b/sys/arm/include/_types.h
--- a/sys/arm/include/_types.h
+++ b/sys/arm/include/_types.h
@@ -41,30 +41,10 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	long long		__int64_t;
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	unsigned long long	__uint64_t;
-
 /*
  * Standard type definitions.
  */
@@ -74,38 +54,19 @@
 typedef	double		__double_t;
 typedef	float		__float_t;
 #endif
-typedef	__int32_t	__intfptr_t;
-typedef	__int64_t	__intmax_t;
-typedef	__int32_t	__intptr_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
-typedef	__int32_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int32_t	__register_t;
 typedef	__int32_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint32_t	__size_t;		/* sizeof() */
-typedef	__int32_t	__ssize_t;		/* byte count or error */
 typedef	__int64_t	__time_t;		/* time()... */
-typedef	__uint32_t	__uintfptr_t;
-typedef	__uint64_t	__uintmax_t;
-typedef	__uint32_t	__uintptr_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 typedef	__uint32_t	__u_register_t;
-typedef	__uint32_t	__vm_offset_t;
 typedef	__uint32_t	__vm_paddr_t;
-typedef	__uint32_t	__vm_size_t;
 
 typedef	unsigned int	___wchar_t;
 #define	__WCHAR_MIN	0		/* min value for a wchar_t */
diff --git a/sys/arm64/include/_types.h b/sys/arm64/include/_types.h
--- a/sys/arm64/include/_types.h
+++ b/sys/arm64/include/_types.h
@@ -35,22 +35,10 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-typedef	long			__int64_t;
-typedef	unsigned long		__uint64_t;
-
 /*
  * Standard type definitions.
  */
@@ -60,38 +48,19 @@
 typedef	double		__double_t;
 typedef	float		__float_t;
 #endif
-typedef	__int64_t	__intfptr_t;
-typedef	__int64_t	__intmax_t;
-typedef	__int64_t	__intptr_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
-typedef	__int64_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int64_t	__register_t;
 typedef	__int64_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint64_t	__size_t;		/* sizeof() */
-typedef	__int64_t	__ssize_t;		/* byte count or error */
 typedef	__int64_t	__time_t;		/* time()... */
-typedef	__uint64_t	__uintfptr_t;
-typedef	__uint64_t	__uintmax_t;
-typedef	__uint64_t	__uintptr_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 typedef	__uint64_t	__u_register_t;
-typedef	__uint64_t	__vm_offset_t;
 typedef	__uint64_t	__vm_paddr_t;
-typedef	__uint64_t	__vm_size_t;
 typedef	unsigned int	___wchar_t;
 
 #define	__WCHAR_MIN	0		/* min value for a wchar_t */
diff --git a/sys/mips/include/_types.h b/sys/mips/include/_types.h
--- a/sys/mips/include/_types.h
+++ b/sys/mips/include/_types.h
@@ -42,33 +42,8 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
-#endif
-
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-#ifdef __mips_n64
-typedef	long			__int64_t;
-typedef	unsigned long		__uint64_t;
-#else
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	long long		__int64_t;
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	unsigned long long	__uint64_t;
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
 /*
@@ -81,22 +56,13 @@
 #endif
 #ifdef __mips_n64
 typedef	__int64_t	__critical_t;
-typedef	__int64_t	__intfptr_t;
-typedef	__int64_t	__intptr_t;
 #else
 typedef	__int32_t	__critical_t;
-typedef	__int32_t	__intfptr_t;
-typedef	__int32_t	__intptr_t;
 #endif
-typedef	__int64_t	__intmax_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
 #if defined(__mips_n64) || defined(__mips_n32)
 typedef	__int64_t	__register_t;
 typedef	__int64_t	f_register_t;
@@ -105,42 +71,20 @@
 typedef	__int32_t	f_register_t;
 #endif
 #ifdef __mips_n64
-typedef	__int64_t	__ptrdiff_t;
 typedef	__int64_t	__segsz_t;
-typedef	__uint64_t	__size_t;
-typedef	__int64_t	__ssize_t;
-typedef	__uint64_t	__uintfptr_t;
-typedef	__uint64_t	__uintptr_t;
 #else
-typedef	__int32_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int32_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint32_t	__size_t;		/* sizeof() */
-typedef	__int32_t	__ssize_t;		/* byte count or error */
-typedef	__uint32_t	__uintfptr_t;
-typedef	__uint32_t	__uintptr_t;
 #endif
 typedef	__int64_t	__time_t;		/* time()... */
-typedef	__uint64_t	__uintmax_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 #if defined(__mips_n64) || defined(__mips_n32)
 typedef	__uint64_t	__u_register_t;
 #else
 typedef	__uint32_t	__u_register_t;
 #endif
-#ifdef __mips_n64
-typedef	__uint64_t	__vm_offset_t;
-typedef	__uint64_t	__vm_size_t;
-#else
-typedef	__uint32_t	__vm_offset_t;
-typedef	__uint32_t	__vm_size_t;
-#endif
 #if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */
 typedef	__uint64_t	__vm_paddr_t;
 #else
diff --git a/sys/powerpc/include/_types.h b/sys/powerpc/include/_types.h
--- a/sys/powerpc/include/_types.h
+++ b/sys/powerpc/include/_types.h
@@ -41,33 +41,8 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
-#endif
-
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-#ifdef __LP64__
-typedef	long			__int64_t;
-typedef	unsigned long		__uint64_t;
-#else
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	long long		__int64_t;
-#ifndef lint
-__extension__
-#endif
-/* LONGLONG */
-typedef	unsigned long long	__uint64_t;
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
 /*
@@ -80,66 +55,35 @@
 #endif
 #ifdef __LP64__
 typedef	__int64_t	__critical_t;
-typedef	__int64_t	__intfptr_t;
-typedef	__int64_t	__intptr_t;
 #else
 typedef	__int32_t	__critical_t;
-typedef	__int32_t	__intfptr_t;
-typedef	__int32_t	__intptr_t;
 #endif
-typedef	__int64_t	__intmax_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
 #ifdef __LP64__
-typedef	__int64_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int64_t	__register_t;
 typedef	__int64_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint64_t	__size_t;		/* sizeof() */
-typedef	__int64_t	__ssize_t;		/* byte count or error */
 #else
-typedef	__int32_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int32_t	__register_t;
 typedef	__int32_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint32_t	__size_t;		/* sizeof() */
-typedef	__int32_t	__ssize_t;		/* byte count or error */
 #endif
 typedef	__int64_t	__time_t;		/* time()... */
-#ifdef __LP64__
-typedef	__uint64_t	__uintfptr_t;
-typedef	__uint64_t	__uintptr_t;
-#else
-typedef	__uint32_t	__uintfptr_t;
-typedef	__uint32_t	__uintptr_t;
-#endif
-typedef	__uint64_t	__uintmax_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 #ifdef __LP64__
 typedef	__uint64_t	__u_register_t;
-typedef	__uint64_t	__vm_offset_t;
 typedef	__uint64_t	__vm_paddr_t;
-typedef	__uint64_t	__vm_size_t;
 #else
 typedef	__uint32_t	__u_register_t;
-typedef	__uint32_t	__vm_offset_t;
 #ifdef BOOKE
 typedef	__uint64_t	__vm_paddr_t;
 #else
 typedef	__uint32_t	__vm_paddr_t;
 #endif
-typedef	__uint32_t	__vm_size_t;
 #endif
 typedef	int		___wchar_t;
 
diff --git a/sys/riscv/include/_types.h b/sys/riscv/include/_types.h
--- a/sys/riscv/include/_types.h
+++ b/sys/riscv/include/_types.h
@@ -35,22 +35,10 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-typedef	long			__int64_t;
-typedef	unsigned long		__uint64_t;
-
 /*
  * Standard type definitions.
  */
@@ -60,38 +48,19 @@
 typedef	double		__double_t;
 typedef	float		__float_t;
 #endif
-typedef	__int64_t	__intfptr_t;
-typedef	__int64_t	__intmax_t;
-typedef	__int64_t	__intptr_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
-typedef	__int64_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int64_t	__register_t;
 typedef	__int64_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint64_t	__size_t;		/* sizeof() */
-typedef	__int64_t	__ssize_t;		/* byte count or error */
 typedef	__int64_t	__time_t;		/* time()... */
-typedef	__uint64_t	__uintfptr_t;
-typedef	__uint64_t	__uintmax_t;
-typedef	__uint64_t	__uintptr_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 typedef	__uint64_t	__u_register_t;
-typedef	__uint64_t	__vm_offset_t;
 typedef	__uint64_t	__vm_paddr_t;
-typedef	__uint64_t	__vm_size_t;
 typedef	int		___wchar_t;
 
 #define	__WCHAR_MIN	__INT_MIN	/* min value for a wchar_t */
diff --git a/sys/sys/_types.h b/sys/sys/_types.h
--- a/sys/sys/_types.h
+++ b/sys/sys/_types.h
@@ -32,6 +32,84 @@
 #define _SYS__TYPES_H_
 
 #include <sys/cdefs.h>
+
+/*
+ * Basic types upon which most other types are built.
+ *
+ * Note: It would be nice to simply use the compiler-provided __FOO_TYPE__
+ * macros. However, in order to do so we have to check that those match the
+ * previous typedefs exactly (not just that they have the same size) since any
+ * change would be an ABI break. For example, changing `long` to `long long`
+ * results in different C++ name mangling.
+ */
+typedef	signed char		__int8_t;
+typedef	unsigned char		__uint8_t;
+typedef	short			__int16_t;
+typedef	unsigned short		__uint16_t;
+typedef	int			__int32_t;
+typedef	unsigned int		__uint32_t;
+#if __SIZEOF_LONG__ == 8
+typedef	long			__int64_t;
+typedef	unsigned long		__uint64_t;
+#elif __SIZEOF_LONG__ == 4
+__extension__
+typedef	long long		__int64_t;
+__extension__
+typedef	unsigned long long	__uint64_t;
+#else
+#error unsupported long size
+#endif
+
+typedef	__int8_t	__int_least8_t;
+typedef	__int16_t	__int_least16_t;
+typedef	__int32_t	__int_least32_t;
+typedef	__int64_t	__int_least64_t;
+typedef	__int64_t	__intmax_t;
+typedef	__uint8_t	__uint_least8_t;
+typedef	__uint16_t	__uint_least16_t;
+typedef	__uint32_t	__uint_least32_t;
+typedef	__uint64_t	__uint_least64_t;
+typedef	__uint64_t	__uintmax_t;
+
+#if __SIZEOF_POINTER__ == 8
+typedef	__int64_t	__intptr_t;
+typedef	__int64_t	__intfptr_t;
+typedef	__uint64_t	__uintptr_t;
+typedef	__uint64_t	__uintfptr_t;
+typedef	__uint64_t	__vm_offset_t;
+typedef	__uint64_t	__vm_size_t;
+#elif __SIZEOF_POINTER__ == 4
+typedef	__int32_t	__intptr_t;
+typedef	__int32_t	__intfptr_t;
+typedef	__uint32_t	__uintptr_t;
+typedef	__uint32_t	__uintfptr_t;
+typedef	__uint32_t	__vm_offset_t;
+typedef	__uint32_t	__vm_size_t;
+#else
+#error unsupported pointer size
+#endif
+
+#if __SIZEOF_SIZE_T__ == 8
+typedef	__uint64_t	__size_t;	/* sizeof() */
+typedef	__int64_t	__ssize_t;	/* byte count or error */
+#elif __SIZEOF_SIZE_T__ == 4
+typedef	__uint32_t	__size_t;	/* sizeof() */
+typedef	__int32_t	__ssize_t;	/* byte count or error */
+#else
+#error unsupported size_t size
+#endif
+
+#if __SIZEOF_PTRDIFF_T__ == 8
+typedef	__int64_t	__ptrdiff_t;	/* ptr1 - ptr2 */
+#elif __SIZEOF_PTRDIFF_T__ == 4
+typedef	__int32_t	__ptrdiff_t;	/* ptr1 - ptr2 */
+#else
+#error unsupported ptrdiff_t size
+#endif
+
+/*
+ * Target-dependent type definitions.
+ */
 #include <machine/_types.h>
 
 /*
diff --git a/sys/sys/stddef.h b/sys/sys/stddef.h
--- a/sys/sys/stddef.h
+++ b/sys/sys/stddef.h
@@ -33,7 +33,7 @@
 
 #include <sys/cdefs.h>
 #include <sys/_null.h>
-#include <machine/_types.h>
+#include <sys/_types.h>
 
 #ifndef _PTRDIFF_T_DECLARED
 typedef	__ptrdiff_t	ptrdiff_t;
diff --git a/sys/x86/include/_types.h b/sys/x86/include/_types.h
--- a/sys/x86/include/_types.h
+++ b/sys/x86/include/_types.h
@@ -41,33 +41,14 @@
 #ifndef _MACHINE__TYPES_H_
 #define	_MACHINE__TYPES_H_
 
-#ifndef _SYS_CDEFS_H_
-#error this file needs sys/cdefs.h as a prerequisite
+#ifndef _SYS__TYPES_H_
+#error do not include this header, use sys/_types.h
 #endif
 
 #include <machine/_limits.h>
 
 #define __NO_STRICT_ALIGNMENT
 
-/*
- * Basic types upon which most other types are built.
- */
-typedef	signed char		__int8_t;
-typedef	unsigned char		__uint8_t;
-typedef	short			__int16_t;
-typedef	unsigned short		__uint16_t;
-typedef	int			__int32_t;
-typedef	unsigned int		__uint32_t;
-#ifdef	__LP64__
-typedef	long			__int64_t;
-typedef	unsigned long		__uint64_t;
-#else
-__extension__
-typedef	long long		__int64_t;
-__extension__
-typedef	unsigned long long	__uint64_t;
-#endif
-
 /*
  * Standard type definitions.
  */
@@ -78,8 +59,6 @@
 typedef	double		__double_t;
 typedef	float		__float_t;
 #endif
-typedef	__int64_t	__intfptr_t;
-typedef	__int64_t	__intptr_t;
 #else
 typedef	unsigned long	__clock_t;
 typedef	__int32_t	__critical_t;
@@ -87,56 +66,30 @@
 typedef	long double	__double_t;
 typedef	long double	__float_t;
 #endif
-typedef	__int32_t	__intfptr_t;
-typedef	__int32_t	__intptr_t;
 #endif
-typedef	__int64_t	__intmax_t;
 typedef	__int32_t	__int_fast8_t;
 typedef	__int32_t	__int_fast16_t;
 typedef	__int32_t	__int_fast32_t;
 typedef	__int64_t	__int_fast64_t;
-typedef	__int8_t	__int_least8_t;
-typedef	__int16_t	__int_least16_t;
-typedef	__int32_t	__int_least32_t;
-typedef	__int64_t	__int_least64_t;
 #ifdef	__LP64__
-typedef	__int64_t	__ptrdiff_t;		/* ptr1 - ptr2 */
 typedef	__int64_t	__register_t;
 typedef	__int64_t	__segsz_t;		/* segment size (in pages) */
-typedef	__uint64_t	__size_t;		/* sizeof() */
-typedef	__int64_t	__ssize_t;		/* byte count or error */
 typedef	__int64_t	__time_t;		/* time()... */
-typedef	__uint64_t	__uintfptr_t;
-typedef	__uint64_t	__uintptr_t;
 #else
-typedef	__int32_t	__ptrdiff_t;
 typedef	__int32_t	__register_t;
 typedef	__int32_t	__segsz_t;
-typedef	__uint32_t	__size_t;
-typedef	__int32_t	__ssize_t;
 typedef	__int32_t	__time_t;
-typedef	__uint32_t	__uintfptr_t;
-typedef	__uint32_t	__uintptr_t;
 #endif
-typedef	__uint64_t	__uintmax_t;
 typedef	__uint32_t	__uint_fast8_t;
 typedef	__uint32_t	__uint_fast16_t;
 typedef	__uint32_t	__uint_fast32_t;
 typedef	__uint64_t	__uint_fast64_t;
-typedef	__uint8_t	__uint_least8_t;
-typedef	__uint16_t	__uint_least16_t;
-typedef	__uint32_t	__uint_least32_t;
-typedef	__uint64_t	__uint_least64_t;
 #ifdef	__LP64__
 typedef	__uint64_t	__u_register_t;
-typedef	__uint64_t	__vm_offset_t;
 typedef	__uint64_t	__vm_paddr_t;
-typedef	__uint64_t	__vm_size_t;
 #else
 typedef	__uint32_t	__u_register_t;
-typedef	__uint32_t	__vm_offset_t;
 typedef	__uint64_t	__vm_paddr_t;
-typedef	__uint32_t	__vm_size_t;
 #endif
 typedef	int		___wchar_t;
 
diff --git a/sys/x86/include/reg.h b/sys/x86/include/reg.h
--- a/sys/x86/include/reg.h
+++ b/sys/x86/include/reg.h
@@ -39,7 +39,7 @@
 #ifndef _MACHINE_REG_H_
 #define	_MACHINE_REG_H_
 
-#include <machine/_types.h>
+#include <sys/_types.h>
 
 #ifdef __i386__
 /*