diff --git a/include/stdio.h b/include/stdio.h
index 362a0dde0634..172a15ecf2b6 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -72,9 +72,6 @@ struct __sbuf {
 	int	_size;
 };
 
-/* hold a buncha junk that would grow the ABI */
-struct __sFILEX;
-
 /*
  * stdio state variables.
  *
@@ -121,7 +118,7 @@ typedef	struct __sFILE {
 
 	/* separate buffer for long sequences of ungetc() */
 	struct	__sbuf _ub;	/* ungetc buffer */
-	struct __sFILEX *_extra; /* additions to FILE to not break ABI */
+	unsigned char	*_up;	/* saved _p when _p is doing ungetc data */
 	int	_ur;		/* saved _r when _r is counting ungetc data */
 
 	/* tricks to meet minimum requirements even when malloc() fails */
@@ -134,6 +131,12 @@ typedef	struct __sFILE {
 	/* Unix stdio files get aligned to block boundaries on fseek() */
 	int	_blksize;	/* stat.st_blksize (may be != _bf._size) */
 	fpos_t	_offset;	/* current lseek offset */
+
+	struct pthread_mutex *_fl_mutex;	/* used for MT-safety */
+	struct pthread *_fl_owner;	/* current owner */
+	int	_fl_count;	/* recursive lock count */
+	int	_orientation;	/* orientation for fwide() */
+	__mbstate_t _mbstate;	/* multibyte conversion state */
 } FILE;
 
 #ifndef _STDSTREAM_DECLARED
diff --git a/lib/libc/stdio/_flock_stub.c b/lib/libc/stdio/_flock_stub.c
index 716ba609aa0d..0b61315dbfc3 100644
--- a/lib/libc/stdio/_flock_stub.c
+++ b/lib/libc/stdio/_flock_stub.c
@@ -55,31 +55,21 @@ __weak_reference(_flockfile_debug_stub, _flockfile_debug);
 __weak_reference(_ftrylockfile, ftrylockfile);
 __weak_reference(_funlockfile, funlockfile);
 
-/*
- * We need to retain binary compatibility for a while.  So pretend
- * that _lock is part of FILE * even though it is dereferenced off
- * _extra now.  When we stop encoding the size of FILE into binaries
- * this can be changed in stdio.h.  This will reduce the amount of
- * code that has to change in the future (just remove this comment
- * and #define).
- */
-#define _lock _extra
-
 void
 _flockfile(FILE *fp)
 {
 	pthread_t curthread = _pthread_self();
 
-	if (fp->_lock->fl_owner == curthread)
-		fp->_lock->fl_count++;
+	if (fp->_fl_owner == curthread)
+		fp->_fl_count++;
 	else {
 		/*
 		 * Make sure this mutex is treated as a private
 		 * internal mutex:
 		 */
-		_pthread_mutex_lock(&fp->_lock->fl_mutex);
-		fp->_lock->fl_owner = curthread;
-		fp->_lock->fl_count = 1;
+		_pthread_mutex_lock(&fp->_fl_mutex);
+		fp->_fl_owner = curthread;
+		fp->_fl_count = 1;
 	}
 }
 
@@ -98,15 +88,15 @@ _ftrylockfile(FILE *fp)
 	pthread_t curthread = _pthread_self();
 	int	ret = 0;
 
-	if (fp->_lock->fl_owner == curthread)
-		fp->_lock->fl_count++;
+	if (fp->_fl_owner == curthread)
+		fp->_fl_count++;
 	/*
 	 * Make sure this mutex is treated as a private
 	 * internal mutex:
 	 */
-	else if (_pthread_mutex_trylock(&fp->_lock->fl_mutex) == 0) {
-		fp->_lock->fl_owner = curthread;
-		fp->_lock->fl_count = 1;
+	else if (_pthread_mutex_trylock(&fp->_fl_mutex) == 0) {
+		fp->_fl_owner = curthread;
+		fp->_fl_count = 1;
 	}
 	else
 		ret = -1;
@@ -121,26 +111,26 @@ _funlockfile(FILE *fp)
 	/*
 	 * Check if this file is owned by the current thread:
 	 */
-	if (fp->_lock->fl_owner == curthread) {
+	if (fp->_fl_owner == curthread) {
 		/*
 		 * Check if this thread has locked the FILE
 		 * more than once:
 		 */
-		if (fp->_lock->fl_count > 1)
+		if (fp->_fl_count > 1)
 			/*
 			 * Decrement the count of the number of
 			 * times the running thread has locked this
 			 * file:
 			 */
-			fp->_lock->fl_count--;
+			fp->_fl_count--;
 		else {
 			/*
 			 * The running thread will release the
 			 * lock now:
 			 */
-			fp->_lock->fl_count = 0;
-			fp->_lock->fl_owner = NULL;
-			_pthread_mutex_unlock(&fp->_lock->fl_mutex);
+			fp->_fl_count = 0;
+			fp->_fl_owner = NULL;
+			_pthread_mutex_unlock(&fp->_fl_mutex);
 		}
 	}
 }
diff --git a/lib/libc/stdio/asprintf.c b/lib/libc/stdio/asprintf.c
index f14265179589..ed8698926f43 100644
--- a/lib/libc/stdio/asprintf.c
+++ b/lib/libc/stdio/asprintf.c
@@ -43,7 +43,6 @@ asprintf(char **str, char const *fmt, ...)
 	int ret;
 	va_list ap;
 	FILE f;
-	struct __sFILEX ext;
 
 	f._file = -1;
 	f._flags = __SWR | __SSTR | __SALC;
@@ -54,8 +53,8 @@ asprintf(char **str, char const *fmt, ...)
 		return (-1);
 	}
 	f._bf._size = f._w = 127;		/* Leave room for the NUL */
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	va_start(ap, fmt);
 	ret = __vfprintf(&f, fmt, ap);		/* Use unlocked __vfprintf */
 	va_end(ap);
diff --git a/lib/libc/stdio/fgetwc.c b/lib/libc/stdio/fgetwc.c
index 719556ad9e1f..3a5b09b9ae7b 100644
--- a/lib/libc/stdio/fgetwc.c
+++ b/lib/libc/stdio/fgetwc.c
@@ -71,7 +71,7 @@ __fgetwc(FILE *fp)
 		return (wc);
 	}
 	do {
-		nconv = __mbrtowc(&wc, fp->_p, fp->_r, &fp->_extra->mbstate);
+		nconv = __mbrtowc(&wc, fp->_p, fp->_r, &fp->_mbstate);
 		if (nconv == (size_t)-1)
 			break;
 		else if (nconv == (size_t)-2)
diff --git a/lib/libc/stdio/fgetws.c b/lib/libc/stdio/fgetws.c
index b6ef01e5c0af..bbc0299d773c 100644
--- a/lib/libc/stdio/fgetws.c
+++ b/lib/libc/stdio/fgetws.c
@@ -62,7 +62,7 @@ fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
 		nl = memchr(fp->_p, '\n', fp->_r);
 		nconv = __mbsnrtowcs(wsp, &src,
 		    nl != NULL ? (nl - fp->_p + 1) : fp->_r,
-		    n - 1, &fp->_extra->mbstate);
+		    n - 1, &fp->_mbstate);
 		if (nconv == (size_t)-1)
 			/* Conversion error */
 			goto error;
@@ -86,7 +86,7 @@ fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
 	if (wsp == ws)
 		/* EOF */
 		goto error;
-	if (!__mbsinit(&fp->_extra->mbstate))
+	if (!__mbsinit(&fp->_mbstate))
 		/* Incomplete character */
 		goto error;
 	*wsp++ = L'\0';
diff --git a/lib/libc/stdio/findfp.c b/lib/libc/stdio/findfp.c
index 73a0d4b2c5e0..a8ce7afb488b 100644
--- a/lib/libc/stdio/findfp.c
+++ b/lib/libc/stdio/findfp.c
@@ -54,36 +54,19 @@ int	__sdidinit;
 #define	NDYNAMIC 10		/* add ten more whenever necessary */
 
 #define	std(flags, file) \
-  	{0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite, \
-	 {0}, __sFX + file}
+  	{0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite}
   /*	 p r w flags file _bf z  cookie      close    read    seek    write */
-  /*     _ub _extra */
+
 				/* the usual - (stdin + stdout + stderr) */
 static FILE usual[FOPEN_MAX - 3];
-static struct __sFILEX usual_extra[FOPEN_MAX - 3];
 static struct glue uglue = { NULL, FOPEN_MAX - 3, usual };
 
-static struct __sFILEX __sFX[3];
-
-/*
- * We can't make this 'static' until 6.0-current due to binary
- * compatibility concerns.  This also means we cannot change the
- * sizeof(FILE) until that time either and must continue to use the
- * __sFILEX stuff to add to FILE.
- */
-FILE __sF[3] = {
+static FILE __sF[3] = {
 	std(__SRD, STDIN_FILENO),
 	std(__SWR, STDOUT_FILENO),
 	std(__SWR|__SNBF, STDERR_FILENO)
 };
 
-/*
- * The following kludge is done to ensure enough binary compatibility
- * with future versions of libc.  Or rather it allows us to work with
- * libraries that have been built with a newer libc that defines these
- * symbols and expects libc to provide them.  We only have need to support
- * i386 because it is the only "old" system we have deployed.
- */
 FILE *__stdinp = &__sF[0];
 FILE *__stdoutp = &__sF[1];
 FILE *__stderrp = &__sF[2];
@@ -109,25 +92,17 @@ moreglue(n)
 {
 	struct glue *g;
 	static FILE empty;
-	static struct __sFILEX emptyx;
 	FILE *p;
-	struct __sFILEX *fx;
 
-	g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE) +
-	    n * sizeof(struct __sFILEX));
+	g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE));
 	if (g == NULL)
 		return (NULL);
 	p = (FILE *)ALIGN(g + 1);
-	fx = (struct __sFILEX *)&p[n];
 	g->next = NULL;
 	g->niobs = n;
 	g->iobs = p;
-	while (--n >= 0) {
-		*p = empty;
-		p->_extra = fx;
-		*p->_extra = emptyx;
-		p++, fx++;
-	}
+	while (--n >= 0)
+		*p++ = empty;
 	return (g);
 }
 
@@ -175,8 +150,8 @@ __sfp()
 	fp->_lb._base = NULL;	/* no line buffer */
 	fp->_lb._size = 0;
 /*	fp->_lock = NULL; */	/* once set always set (reused) */
-	fp->_extra->orientation = 0;
-	memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
+	fp->_orientation = 0;
+	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
 	return (fp);
 }
 
@@ -229,17 +204,8 @@ _cleanup()
 void
 __sinit()
 {
-	int	i;
 
-	THREAD_LOCK();
-	if (__sdidinit == 0) {
-		/* Set _extra for the usual suspects. */
-		for (i = 0; i < FOPEN_MAX - 3; i++)
-			usual[i]._extra = &usual_extra[i];
-
-		/* Make sure we clean up on exit. */
-		__cleanup = _cleanup;		/* conservative */
-		__sdidinit = 1;
-	}
-	THREAD_UNLOCK();
+	/* Make sure we clean up on exit. */
+	__cleanup = _cleanup;		/* conservative */
+	__sdidinit = 1;
 }
diff --git a/lib/libc/stdio/fputwc.c b/lib/libc/stdio/fputwc.c
index 0848b74998d1..ae92f662822c 100644
--- a/lib/libc/stdio/fputwc.c
+++ b/lib/libc/stdio/fputwc.c
@@ -56,8 +56,7 @@ __fputwc(wchar_t wc, FILE *fp)
 		*buf = (unsigned char)wc;
 		len = 1;
 	} else {
-		if ((len = __wcrtomb(buf, wc, &fp->_extra->mbstate)) ==
-		    (size_t)-1) {
+		if ((len = __wcrtomb(buf, wc, &fp->_mbstate)) == (size_t)-1) {
 			fp->_flags |= __SERR;
 			return (WEOF);
 		}
diff --git a/lib/libc/stdio/fputws.c b/lib/libc/stdio/fputws.c
index 025e1c00d198..73974113253a 100644
--- a/lib/libc/stdio/fputws.c
+++ b/lib/libc/stdio/fputws.c
@@ -55,7 +55,7 @@ fputws(const wchar_t * __restrict ws, FILE * __restrict fp)
 	iov.iov_base = buf;
 	do {
 		nbytes = __wcsnrtombs(buf, &ws, SIZE_T_MAX, sizeof(buf),
-		    &fp->_extra->mbstate);
+		    &fp->_mbstate);
 		if (nbytes == (size_t)-1)
 			goto error;
 		iov.iov_len = uio.uio_resid = nbytes;
diff --git a/lib/libc/stdio/freopen.c b/lib/libc/stdio/freopen.c
index 45f7d84c9020..d7184969a649 100644
--- a/lib/libc/stdio/freopen.c
+++ b/lib/libc/stdio/freopen.c
@@ -182,8 +182,8 @@ freopen(file, mode, fp)
 	if (HASLB(fp))
 		FREELB(fp);
 	fp->_lb._size = 0;
-	fp->_extra->orientation = 0;
-	memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
+	fp->_orientation = 0;
+	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
 
 	if (f < 0) {			/* did not get it after all */
 		fp->_flags = 0;		/* set it free */
diff --git a/lib/libc/stdio/fseek.c b/lib/libc/stdio/fseek.c
index 8482d0d57d36..c9343490e6b0 100644
--- a/lib/libc/stdio/fseek.c
+++ b/lib/libc/stdio/fseek.c
@@ -233,7 +233,7 @@ _fseeko(fp, offset, whence, ltest)
 	 */
 	if (HASUB(fp)) {
 		curoff += fp->_r;	/* kill off ungetc */
-		n = fp->_extra->_up - fp->_bf._base;
+		n = fp->_up - fp->_bf._base;
 		curoff -= n;
 		n += fp->_ur;
 	} else {
@@ -255,7 +255,7 @@ _fseeko(fp, offset, whence, ltest)
 		if (HASUB(fp))
 			FREEUB(fp);
 		fp->_flags &= ~__SEOF;
-		memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
+		memset(&fp->_mbstate, 0, sizeof(mbstate_t));
 		return (0);
 	}
 
@@ -283,7 +283,7 @@ _fseeko(fp, offset, whence, ltest)
 		fp->_r -= n;
 	}
 	fp->_flags &= ~__SEOF;
-	memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
+	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
 	return (0);
 
 	/*
@@ -306,6 +306,6 @@ _fseeko(fp, offset, whence, ltest)
 	fp->_r = 0;
 	/* fp->_w = 0; */	/* unnecessary (I think...) */
 	fp->_flags &= ~__SEOF;
-	memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
+	memset(&fp->_mbstate, 0, sizeof(mbstate_t));
 	return (0);
 }
diff --git a/lib/libc/stdio/fwide.c b/lib/libc/stdio/fwide.c
index 70309f56daa1..c94ffe63a1bc 100644
--- a/lib/libc/stdio/fwide.c
+++ b/lib/libc/stdio/fwide.c
@@ -42,9 +42,9 @@ fwide(FILE *fp, int mode)
 
 	FLOCKFILE(fp);
 	/* Only change the orientation if the stream is not oriented yet. */
-	if (mode != 0 && fp->_extra->orientation == 0)
-		fp->_extra->orientation = mode > 0 ? 1 : -1;
-	m = fp->_extra->orientation;
+	if (mode != 0 && fp->_orientation == 0)
+		fp->_orientation = mode > 0 ? 1 : -1;
+	m = fp->_orientation;
 	FUNLOCKFILE(fp);
 
 	return (m);
diff --git a/lib/libc/stdio/local.h b/lib/libc/stdio/local.h
index 9d2ff0f00083..09b3a1869afc 100644
--- a/lib/libc/stdio/local.h
+++ b/lib/libc/stdio/local.h
@@ -80,16 +80,6 @@ extern size_t	__fread(void * __restrict buf, size_t size, size_t count,
 extern int	__sdidinit;
 
 
-/* hold a buncha junk that would grow the ABI */
-struct __sFILEX {
-	unsigned char	*_up;	/* saved _p when _p is doing ungetc data */
-	pthread_mutex_t	fl_mutex;	/* used for MT-safety */
-	pthread_t	fl_owner;	/* current owner */
-	int		fl_count;	/* recursive lock count */
-	int		orientation;	/* orientation for fwide() */
-	mbstate_t	mbstate;	/* multibyte conversion state */
-};
-
 /*
  * Prepare the given FILE for writing, and return 0 iff it
  * can be written now.  Otherwise, return EOF and set errno.
@@ -119,20 +109,11 @@ struct __sFILEX {
 	(fp)->_lb._base = NULL; \
 }
 
-#define	INITEXTRA(fp) { \
-	(fp)->_extra->_up = NULL; \
-	(fp)->_extra->fl_mutex = PTHREAD_MUTEX_INITIALIZER; \
-	(fp)->_extra->fl_owner = NULL; \
-	(fp)->_extra->fl_count = 0; \
-	(fp)->_extra->orientation = 0; \
-	memset(&(fp)->_extra->mbstate, 0, sizeof(mbstate_t)); \
-}
-
 /*
  * Set the orientation for a stream. If o > 0, the stream has wide-
  * orientation. If o < 0, the stream has byte-orientation.
  */
 #define	ORIENT(fp, o)	do {				\
-	if ((fp)->_extra->orientation == 0)		\
-		(fp)->_extra->orientation = (o);	\
+	if ((fp)->_orientation == 0)			\
+		(fp)->_orientation = (o);		\
 } while (0)
diff --git a/lib/libc/stdio/refill.c b/lib/libc/stdio/refill.c
index a4f649bafbc8..f2a1f16f21e6 100644
--- a/lib/libc/stdio/refill.c
+++ b/lib/libc/stdio/refill.c
@@ -106,7 +106,7 @@ __srefill(FILE *fp)
 		if (HASUB(fp)) {
 			FREEUB(fp);
 			if ((fp->_r = fp->_ur) != 0) {
-				fp->_p = fp->_extra->_up;
+				fp->_p = fp->_up;
 				return (0);
 			}
 		}
diff --git a/lib/libc/stdio/snprintf.c b/lib/libc/stdio/snprintf.c
index c430ab189348..0470a332cd14 100644
--- a/lib/libc/stdio/snprintf.c
+++ b/lib/libc/stdio/snprintf.c
@@ -49,7 +49,6 @@ snprintf(char * __restrict str, size_t n, char const * __restrict fmt, ...)
 	int ret;
 	va_list ap;
 	FILE f;
-	struct __sFILEX ext;
 
 	on = n;
 	if (n != 0)
@@ -61,8 +60,8 @@ snprintf(char * __restrict str, size_t n, char const * __restrict fmt, ...)
 	f._flags = __SWR | __SSTR;
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = n;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	ret = __vfprintf(&f, fmt, ap);
 	if (on > 0)
 		*f._p = '\0';
diff --git a/lib/libc/stdio/sprintf.c b/lib/libc/stdio/sprintf.c
index f49259f97ce7..aaaae5535d2c 100644
--- a/lib/libc/stdio/sprintf.c
+++ b/lib/libc/stdio/sprintf.c
@@ -47,14 +47,13 @@ sprintf(char * __restrict str, char const * __restrict fmt, ...)
 	int ret;
 	va_list ap;
 	FILE f;
-	struct __sFILEX ext;
 
 	f._file = -1;
 	f._flags = __SWR | __SSTR;
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = INT_MAX;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	va_start(ap, fmt);
 	ret = __vfprintf(&f, fmt, ap);
 	va_end(ap);
diff --git a/lib/libc/stdio/sscanf.c b/lib/libc/stdio/sscanf.c
index a1ee11d35d62..3c792e054ba5 100644
--- a/lib/libc/stdio/sscanf.c
+++ b/lib/libc/stdio/sscanf.c
@@ -59,7 +59,6 @@ sscanf(const char * __restrict str, char const * __restrict fmt, ...)
 {
 	int ret;
 	va_list ap;
-	struct __sFILEX extra;
 	FILE f;
 
 	f._file = -1;
@@ -69,8 +68,8 @@ sscanf(const char * __restrict str, char const * __restrict fmt, ...)
 	f._read = eofread;
 	f._ub._base = NULL;
 	f._lb._base = NULL;
-	f._extra = &extra;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	va_start(ap, fmt);
 	ret = __svfscanf(&f, fmt, ap);
 	va_end(ap);
diff --git a/lib/libc/stdio/ungetc.c b/lib/libc/stdio/ungetc.c
index ef2c68b93583..1353b7ecd7a3 100644
--- a/lib/libc/stdio/ungetc.c
+++ b/lib/libc/stdio/ungetc.c
@@ -158,7 +158,7 @@ __ungetc(int c, FILE *fp)
 	 * Initially, we will use the `reserve' buffer.
 	 */
 	fp->_ur = fp->_r;
-	fp->_extra->_up = fp->_p;
+	fp->_up = fp->_p;
 	fp->_ub._base = fp->_ubuf;
 	fp->_ub._size = sizeof(fp->_ubuf);
 	fp->_ubuf[sizeof(fp->_ubuf) - 1] = c;
diff --git a/lib/libc/stdio/ungetwc.c b/lib/libc/stdio/ungetwc.c
index 510648b8ded4..10dbbbf89a5a 100644
--- a/lib/libc/stdio/ungetwc.c
+++ b/lib/libc/stdio/ungetwc.c
@@ -49,7 +49,7 @@ __ungetwc(wint_t wc, FILE *fp)
 
 	if (wc == WEOF)
 		return (WEOF);
-	if ((len = __wcrtomb(buf, wc, &fp->_extra->mbstate)) == (size_t)-1) {
+	if ((len = __wcrtomb(buf, wc, &fp->_mbstate)) == (size_t)-1) {
 		fp->_flags |= __SERR;
 		return (WEOF);
 	}
diff --git a/lib/libc/stdio/vasprintf.c b/lib/libc/stdio/vasprintf.c
index 01ac06889c3e..0682b5b6a1cc 100644
--- a/lib/libc/stdio/vasprintf.c
+++ b/lib/libc/stdio/vasprintf.c
@@ -43,7 +43,6 @@ vasprintf(str, fmt, ap)
 {
 	int ret;
 	FILE f;
-	struct __sFILEX ext;
 
 	f._file = -1;
 	f._flags = __SWR | __SSTR | __SALC;
@@ -54,8 +53,8 @@ vasprintf(str, fmt, ap)
 		return (-1);
 	}
 	f._bf._size = f._w = 127;		/* Leave room for the NUL */
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	ret = __vfprintf(&f, fmt, ap);
 	if (ret < 0) {
 		free(f._bf._base);
diff --git a/lib/libc/stdio/vfprintf.c b/lib/libc/stdio/vfprintf.c
index 45e7c7fbc14c..feba233039dd 100644
--- a/lib/libc/stdio/vfprintf.c
+++ b/lib/libc/stdio/vfprintf.c
@@ -149,7 +149,8 @@ __sbprintf(FILE *fp, const char *fmt, va_list ap)
 	fake._file = fp->_file;
 	fake._cookie = fp->_cookie;
 	fake._write = fp->_write;
-	fake._extra = fp->_extra;
+	fake._orientation = fp->_orientation;
+	fake._mbstate = fp->_mbstate;
 
 	/* set up the buffer */
 	fake._bf._base = fake._p = buf;
diff --git a/lib/libc/stdio/vfwprintf.c b/lib/libc/stdio/vfwprintf.c
index b4ed1a8e498e..525186a13840 100644
--- a/lib/libc/stdio/vfwprintf.c
+++ b/lib/libc/stdio/vfwprintf.c
@@ -132,7 +132,8 @@ __sbprintf(FILE *fp, const wchar_t *fmt, va_list ap)
 	fake._file = fp->_file;
 	fake._cookie = fp->_cookie;
 	fake._write = fp->_write;
-	fake._extra = fp->_extra;
+	fake._orientation = fp->_orientation;
+	fake._mbstate = fp->_mbstate;
 
 	/* set up the buffer */
 	fake._bf._base = fake._p = buf;
diff --git a/lib/libc/stdio/vsnprintf.c b/lib/libc/stdio/vsnprintf.c
index ba15c34ffa3b..f990664146c9 100644
--- a/lib/libc/stdio/vsnprintf.c
+++ b/lib/libc/stdio/vsnprintf.c
@@ -48,7 +48,6 @@ vsnprintf(char * __restrict str, size_t n, const char * __restrict fmt,
 	int ret;
 	char dummy[2];
 	FILE f;
-	struct __sFILEX ext;
 
 	on = n;
 	if (n != 0)
@@ -66,8 +65,8 @@ vsnprintf(char * __restrict str, size_t n, const char * __restrict fmt,
 	f._flags = __SWR | __SSTR;
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = n;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	ret = __vfprintf(&f, fmt, ap);
 	if (on > 0)
 		*f._p = '\0';
diff --git a/lib/libc/stdio/vsprintf.c b/lib/libc/stdio/vsprintf.c
index 923afd814369..60d830c38eaa 100644
--- a/lib/libc/stdio/vsprintf.c
+++ b/lib/libc/stdio/vsprintf.c
@@ -45,14 +45,13 @@ vsprintf(char * __restrict str, const char * __restrict fmt, __va_list ap)
 {
 	int ret;
 	FILE f;
-	struct __sFILEX ext;
 
 	f._file = -1;
 	f._flags = __SWR | __SSTR;
 	f._bf._base = f._p = (unsigned char *)str;
 	f._bf._size = f._w = INT_MAX;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	ret = __vfprintf(&f, fmt, ap);
 	*f._p = 0;
 	return (ret);
diff --git a/lib/libc/stdio/vsscanf.c b/lib/libc/stdio/vsscanf.c
index 1f4b80bdad90..e5e96917b42f 100644
--- a/lib/libc/stdio/vsscanf.c
+++ b/lib/libc/stdio/vsscanf.c
@@ -61,7 +61,6 @@ vsscanf(str, fmt, ap)
 	__va_list ap;
 {
 	FILE f;
-	struct __sFILEX ext;
 
 	f._file = -1;
 	f._flags = __SRD;
@@ -70,7 +69,7 @@ vsscanf(str, fmt, ap)
 	f._read = eofread;
 	f._ub._base = NULL;
 	f._lb._base = NULL;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	return (__svfscanf(&f, fmt, ap));
 }
diff --git a/lib/libc/stdio/vswprintf.c b/lib/libc/stdio/vswprintf.c
index 1d8a64ed4c11..61b8720bb9ca 100644
--- a/lib/libc/stdio/vswprintf.c
+++ b/lib/libc/stdio/vswprintf.c
@@ -46,7 +46,6 @@ vswprintf(wchar_t * __restrict s, size_t n, const wchar_t * __restrict fmt,
 	static const mbstate_t initial;
 	mbstate_t mbs;
 	FILE f;
-	struct __sFILEX ext;
 	char *mbp;
 	int ret, sverrno;
 	size_t nwc;
@@ -64,8 +63,8 @@ vswprintf(wchar_t * __restrict s, size_t n, const wchar_t * __restrict fmt,
 		return (-1);
 	}
 	f._bf._size = f._w = 127;		/* Leave room for the NUL */
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	ret = __vfwprintf(&f, fmt, ap);
 	if (ret < 0) {
 		sverrno = errno;
diff --git a/lib/libc/stdio/vswscanf.c b/lib/libc/stdio/vswscanf.c
index 5d9a22a5b0d3..67bfb47b68d4 100644
--- a/lib/libc/stdio/vswscanf.c
+++ b/lib/libc/stdio/vswscanf.c
@@ -63,7 +63,6 @@ vswscanf(const wchar_t * __restrict str, const wchar_t * __restrict fmt,
 	static const mbstate_t initial;
 	mbstate_t mbs;
 	FILE f;
-	struct __sFILEX ext;
 	char *mbstr;
 	size_t mlen;
 	int r;
@@ -86,8 +85,8 @@ vswscanf(const wchar_t * __restrict str, const wchar_t * __restrict fmt,
 	f._read = eofread;
 	f._ub._base = NULL;
 	f._lb._base = NULL;
-	f._extra = &ext;
-	INITEXTRA(&f);
+	f._orientation = 0;
+	memset(&f._mbstate, 0, sizeof(mbstate_t));
 	r = __vfwscanf(&f, fmt, ap);
 	free(mbstr);
 
diff --git a/lib/libc/stdio/xprintf.c b/lib/libc/stdio/xprintf.c
index 41ee4abca39d..df4b7d224edf 100644
--- a/lib/libc/stdio/xprintf.c
+++ b/lib/libc/stdio/xprintf.c
@@ -583,7 +583,8 @@ __v3printf(FILE *fp, const char *fmt, int pct, va_list ap)
 	fake._file = fp->_file;
 	fake._cookie = fp->_cookie;
 	fake._write = fp->_write;
-	fake._extra = fp->_extra;
+	fake._orientation = fp->_orientation;
+	fake._mbstate = fp->_mbstate;
 
 	/* set up the buffer */
 	fake._bf._base = fake._p = buf;