From: guenther <guenther@openbsd.org>
Date: Wed, 29 Nov 2017 05:13:57 +0000 (+0000)
Subject: clang doesn't propagate attributes like "asm labels" and "visibility(hidden)"
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=ea6088e7d368d53c49ebfdf4520275cec2f78f5b;p=openbsd

clang doesn't propagate attributes like "asm labels" and "visibility(hidden)"
to builtins like mem{set,cpy,move} and __stack_smash_handler.  So, when
building with clang, instead mark those as protected visibility to get rid
of the PLT relocations.  We can't take the address of them then, but that's
ok: it's a build-time error not a run-time error.

ok kettenis@
---

diff --git a/lib/libc/arch/amd64/DEFS.h b/lib/libc/arch/amd64/DEFS.h
index 9a2daa3d424..8e39fc58122 100644
--- a/lib/libc/arch/amd64/DEFS.h
+++ b/lib/libc/arch/amd64/DEFS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: DEFS.h,v 1.1 2015/11/14 21:53:03 guenther Exp $	*/
+/*	$OpenBSD: DEFS.h,v 1.2 2017/11/29 05:13:57 guenther Exp $	*/
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -55,7 +55,15 @@
  * For functions implemented in ASM that aren't syscalls.
  *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
  *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
+ *   END_BUILTIN(x)	If compiling with clang, then just END() and
+ *			mark it .protected, else be like END_STRONG();
+ *			for clang builtins like memcpy
  */
 #define	END_STRONG(x)	END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x))
 #define	END_WEAK(x)	END_STRONG(x); .weak x
 
+#ifdef __clang__
+#define	END_BUILTIN(x)	END(x); .protected x
+#else
+#define	END_BUILTIN(x)	END_STRONG(x)
+#endif
diff --git a/lib/libc/arch/amd64/string/memmove.S b/lib/libc/arch/amd64/string/memmove.S
index f0e01654c2f..da244c332a1 100644
--- a/lib/libc/arch/amd64/string/memmove.S
+++ b/lib/libc/arch/amd64/string/memmove.S
@@ -51,12 +51,14 @@ ENTRY(memmove)
 	subq	%rsi,%rax
 	cmpq	%rcx,%rax	/* overlapping? */
 	jb	1f
+#ifdef memcpy_in_asm
 	jmp	2f		/* nope */
 
-// ENTRY(memcpy)
+ENTRY(memcpy)
 	movq	%rdi,%r11	/* save dest */
 	movq	%rdx,%rcx
 2:
+#endif
 	cld			/* copy forwards. */
 	shrq	$3,%rcx		/* copy by words */
 	rep
@@ -85,6 +87,8 @@ ENTRY(memmove)
 	movq	%r11,%rax
 	cld
 	ret
-// END(memcpy)
-END_STRONG(memmove)
+#ifdef memcpy_in_asm
+END_BUILTIN(memcpy)
+#endif
+END_BUILTIN(memmove)
 END_WEAK(bcopy)
diff --git a/lib/libc/arch/amd64/string/memset.S b/lib/libc/arch/amd64/string/memset.S
index b3f4ffa17bf..2a8645cb1c3 100644
--- a/lib/libc/arch/amd64/string/memset.S
+++ b/lib/libc/arch/amd64/string/memset.S
@@ -53,4 +53,4 @@ L1:	rep
 	movq	%r11,%rax
 
 	ret
-END_STRONG(memset)
+END_BUILTIN(memset)
diff --git a/lib/libc/arch/arm/DEFS.h b/lib/libc/arch/arm/DEFS.h
index 828c9cd68aa..4220bdf2d37 100644
--- a/lib/libc/arch/arm/DEFS.h
+++ b/lib/libc/arch/arm/DEFS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: DEFS.h,v 1.1 2016/08/06 19:16:09 guenther Exp $	*/
+/*	$OpenBSD: DEFS.h,v 1.2 2017/11/29 05:13:57 guenther Exp $	*/
 /*
  * Copyright (c) 2016 Philip Guenther <guenther@openbsd.org>
  *
@@ -35,6 +35,15 @@
  * For functions implemented in ASM that aren't syscalls.
  *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
  *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
+ *   END_BUILTIN(x)	If compiling with clang, then just END() and
+ *			mark it .protected, else be like END_STRONG();
+ *			for clang builtins like memcpy
  */
 #define	END_STRONG(x)	END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x))
 #define	END_WEAK(x)	END_STRONG(x); .weak x
+ 
+#ifdef __clang__
+#define	END_BUILTIN(x)	END(x); .protected x
+#else
+#define	END_BUILTIN(x)	END_STRONG(x)
+#endif
diff --git a/lib/libc/arch/arm/string/memcpy.S b/lib/libc/arch/arm/string/memcpy.S
index d1f557980a7..aba898b40a7 100644
--- a/lib/libc/arch/arm/string/memcpy.S
+++ b/lib/libc/arch/arm/string/memcpy.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memcpy.S,v 1.7 2017/10/29 02:21:33 guenther Exp $	*/
+/*	$OpenBSD: memcpy.S,v 1.8 2017/11/29 05:13:57 guenther Exp $	*/
 /*	$NetBSD: memcpy.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*-
@@ -42,4 +42,4 @@ ENTRY(memcpy)
 	stmfd	sp!, {r0, lr}
 	bl	_memcpy
 	ldmfd	sp!, {r0, pc}
-END_STRONG(memcpy)
+END_BUILTIN(memcpy)
diff --git a/lib/libc/arch/arm/string/memmove.S b/lib/libc/arch/arm/string/memmove.S
index 95eca35bbde..1dfd4108105 100644
--- a/lib/libc/arch/arm/string/memmove.S
+++ b/lib/libc/arch/arm/string/memmove.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memmove.S,v 1.6 2017/10/29 02:21:33 guenther Exp $	*/
+/*	$OpenBSD: memmove.S,v 1.7 2017/11/29 05:13:57 guenther Exp $	*/
 /*	$NetBSD: memmove.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*-
@@ -36,4 +36,4 @@ ENTRY(memmove)
 	stmfd	sp!, {r0, lr}
 	bl	_memcpy
 	ldmfd	sp!, {r0, pc}
-END_STRONG(memmove)
+END_BUILTIN(memmove)
diff --git a/lib/libc/arch/arm/string/memset.S b/lib/libc/arch/arm/string/memset.S
index 573e924209d..91511f117f1 100644
--- a/lib/libc/arch/arm/string/memset.S
+++ b/lib/libc/arch/arm/string/memset.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memset.S,v 1.5 2016/08/06 19:16:09 guenther Exp $	*/
+/*	$OpenBSD: memset.S,v 1.6 2017/11/29 05:13:57 guenther Exp $	*/
 /*	$NetBSD: memset.S,v 1.3 2003/04/05 23:08:52 bjh21 Exp $	*/
 
 /*
@@ -127,4 +127,4 @@ ENTRY(memset)
 
 	ldmfd	sp!, {r0}
 	mov	pc, lr			/* Exit */
-END_STRONG(memset)
+END_BUILTIN(memset)
diff --git a/lib/libc/arch/i386/DEFS.h b/lib/libc/arch/i386/DEFS.h
index 051613308e3..db2d9696d1d 100644
--- a/lib/libc/arch/i386/DEFS.h
+++ b/lib/libc/arch/i386/DEFS.h
@@ -1,3 +1,49 @@
-/*	$OpenBSD: DEFS.h,v 1.2 1996/08/19 08:12:09 tholo Exp $ */
+/*	$OpenBSD: DEFS.h,v 1.3 2017/11/29 05:13:57 guenther Exp $ */
+/*
+ * Copyright (c) 2017 Philip Guenther <guenther@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
 
 #include <machine/asm.h>
+
+/*
+ * We define a hidden alias with the prefix "_libc_" for each global symbol
+ * that may be used internally.  By referencing _libc_x instead of x, other
+ * parts of libc prevent overriding by the application and avoid unnecessary
+ * relocations.
+ */
+#define _HIDDEN(x)		_libc_##x
+#define _HIDDEN_ALIAS(x,y)			\
+	STRONG_ALIAS(_HIDDEN(x),y);		\
+	.hidden _HIDDEN(x)
+#define _HIDDEN_FALIAS(x,y)			\
+	_HIDDEN_ALIAS(x,y);			\
+	.type _HIDDEN(x),@function
+
+/*
+ * For functions implemented in ASM that aren't syscalls.
+ *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
+ *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
+ *   END_BUILTIN(x)	If compiling with clang, then just END() and
+ *			mark it .protected, else be like END_STRONG();
+ *			for clang builtins like memcpy
+ */
+#define	END_STRONG(x)	END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x))
+#define	END_WEAK(x)	END_STRONG(x); .weak x
+
+#ifdef __clang__
+#define	END_BUILTIN(x)	END(x); .protected x
+#else
+#define	END_BUILTIN(x)	END_STRONG(x)
+#endif
diff --git a/lib/libc/arch/i386/SYS.h b/lib/libc/arch/i386/SYS.h
index 3ecba9830e4..993ad31715d 100644
--- a/lib/libc/arch/i386/SYS.h
+++ b/lib/libc/arch/i386/SYS.h
@@ -29,37 +29,14 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$OpenBSD: SYS.h,v 1.26 2017/06/01 12:14:48 naddy Exp $
+ *	$OpenBSD: SYS.h,v 1.27 2017/11/29 05:13:57 guenther Exp $
  */
 
-#include <machine/asm.h>
+#include "DEFS.h"
 #include <sys/syscall.h>
 
 #define TCB_OFFSET_ERRNO	16
 
-/*
- * We define a hidden alias with the prefix "_libc_" for each global symbol
- * that may be used internally.  By referencing _libc_x instead of x, other
- * parts of libc prevent overriding by the application and avoid unnecessary
- * relocations.
- */
-#define _HIDDEN(x)		_libc_##x
-#define _HIDDEN_ALIAS(x,y)			\
-	STRONG_ALIAS(_HIDDEN(x),y);		\
-	.hidden _HIDDEN(x)
-#define _HIDDEN_FALIAS(x,y)			\
-	_HIDDEN_ALIAS(x,y);			\
-	.type _HIDDEN(x),@function
-
-/*
- * For functions implemented in ASM that aren't syscalls.
- *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
- *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
- */
-#define	END_STRONG(x)	END(x); _HIDDEN_FALIAS(x,x); END(_HIDDEN(x))
-#define	END_WEAK(x)	END_STRONG(x); .weak x
-
-
 /*
  * Design note:
  *
diff --git a/lib/libc/arch/i386/gen/flt_rounds.S b/lib/libc/arch/i386/gen/flt_rounds.S
index a46fe912fd5..7cba4a3f379 100644
--- a/lib/libc/arch/i386/gen/flt_rounds.S
+++ b/lib/libc/arch/i386/gen/flt_rounds.S
@@ -1,10 +1,10 @@
-/* $OpenBSD: flt_rounds.S,v 1.6 2017/08/19 18:23:00 deraadt Exp $ */
+/* $OpenBSD: flt_rounds.S,v 1.7 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin, Apr 4, 1995
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 	.section .rodata
 	.align 2
diff --git a/lib/libc/arch/i386/stdlib/abs.S b/lib/libc/arch/i386/stdlib/abs.S
index 5403c642d1d..235ce5d9879 100644
--- a/lib/libc/arch/i386/stdlib/abs.S
+++ b/lib/libc/arch/i386/stdlib/abs.S
@@ -30,7 +30,7 @@
  * SUCH DAMAGE.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(abs)
 	movl	4(%esp),%eax
diff --git a/lib/libc/arch/i386/stdlib/div.S b/lib/libc/arch/i386/stdlib/div.S
index 6c05fc34462..5227bfe3b9c 100644
--- a/lib/libc/arch/i386/stdlib/div.S
+++ b/lib/libc/arch/i386/stdlib/div.S
@@ -3,7 +3,7 @@
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(div)
 	movl	4(%esp),%eax
diff --git a/lib/libc/arch/i386/stdlib/labs.S b/lib/libc/arch/i386/stdlib/labs.S
index 980ecf3426a..d7e592822b4 100644
--- a/lib/libc/arch/i386/stdlib/labs.S
+++ b/lib/libc/arch/i386/stdlib/labs.S
@@ -30,7 +30,7 @@
  * SUCH DAMAGE.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(labs)
 	movl	4(%esp),%eax
diff --git a/lib/libc/arch/i386/stdlib/ldiv.S b/lib/libc/arch/i386/stdlib/ldiv.S
index 48db16098af..3c2e84767c2 100644
--- a/lib/libc/arch/i386/stdlib/ldiv.S
+++ b/lib/libc/arch/i386/stdlib/ldiv.S
@@ -3,7 +3,7 @@
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(ldiv)
 	movl	4(%esp),%eax
diff --git a/lib/libc/arch/i386/string/bcmp.S b/lib/libc/arch/i386/string/bcmp.S
index b55c93a6e14..6a9772e0a48 100644
--- a/lib/libc/arch/i386/string/bcmp.S
+++ b/lib/libc/arch/i386/string/bcmp.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: bcmp.S,v 1.4 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: bcmp.S,v 1.5 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(bcmp)
 	pushl	%edi
diff --git a/lib/libc/arch/i386/string/bzero.S b/lib/libc/arch/i386/string/bzero.S
index 43251b5cdff..75cbf72278b 100644
--- a/lib/libc/arch/i386/string/bzero.S
+++ b/lib/libc/arch/i386/string/bzero.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: bzero.S,v 1.5 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: bzero.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(bzero)
 	pushl	%edi
diff --git a/lib/libc/arch/i386/string/ffs.S b/lib/libc/arch/i386/string/ffs.S
index 7befc0bcbbe..b02405ee2ef 100644
--- a/lib/libc/arch/i386/string/ffs.S
+++ b/lib/libc/arch/i386/string/ffs.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: ffs.S,v 1.5 2017/08/19 18:25:50 deraadt Exp $ */
+/*	$OpenBSD: ffs.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(ffs)
 	bsfl	4(%esp),%eax
diff --git a/lib/libc/arch/i386/string/memchr.S b/lib/libc/arch/i386/string/memchr.S
index b3d773bea4c..660f0373153 100644
--- a/lib/libc/arch/i386/string/memchr.S
+++ b/lib/libc/arch/i386/string/memchr.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: memchr.S,v 1.5 2017/08/19 18:25:50 deraadt Exp $ */
+/*	$OpenBSD: memchr.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(memchr)
 	pushl	%edi
diff --git a/lib/libc/arch/i386/string/memcmp.S b/lib/libc/arch/i386/string/memcmp.S
index 171af0734b1..a5f2c36bdd7 100644
--- a/lib/libc/arch/i386/string/memcmp.S
+++ b/lib/libc/arch/i386/string/memcmp.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: memcmp.S,v 1.5 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: memcmp.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(memcmp)
 	pushl	%edi
diff --git a/lib/libc/arch/i386/string/memmove.S b/lib/libc/arch/i386/string/memmove.S
index afa465aa4dd..8d124ad76a9 100644
--- a/lib/libc/arch/i386/string/memmove.S
+++ b/lib/libc/arch/i386/string/memmove.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memmove.S,v 1.6 2015/08/31 02:53:56 guenther Exp $	*/
+/*	$OpenBSD: memmove.S,v 1.7 2017/11/29 05:13:57 guenther Exp $	*/
 
 /*-
  * Copyright (c) 1993, 1994, 1995 Charles M. Hannum.  All rights reserved.
@@ -33,7 +33,7 @@
  * SUCH DAMAGE.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 /*
  * Emulate bcopy() by swapping the first two arguments, and jumping
@@ -61,17 +61,20 @@ docopy:
 	subl	%esi,%eax
 	cmpl	%ecx,%eax		# overlapping?
 	jb	1f
+#ifdef memcpy_in_asm
 	jmp	docopyf			# nope
+
 /*
  * memcpy() doesn't worry about overlap and always copies forward
  */
-// ENTRY(memcpy)
+ENTRY(memcpy)
 	pushl	%esi
 	pushl	%edi
 	movl	12(%esp),%edi
 	movl	16(%esp),%esi
 	movl	20(%esp),%ecx
 docopyf:
+#endif
 	movl	%edi,%eax		# setup return value for memcpy/memmove
 	shrl	$2,%ecx			# copy by 32-bit words
 	rep
@@ -104,5 +107,8 @@ docopyf:
 	popl	%esi
 	cld
 	ret
-END_STRONG(memmove)
+#ifdef memcpy_in_asm
+END_BUILTIN(memcpy)
+#endif
+END_BUILTIN(memmove)
 END_WEAK(bcopy)
diff --git a/lib/libc/arch/i386/string/memset.S b/lib/libc/arch/i386/string/memset.S
index 0eb4381558e..5103b616054 100644
--- a/lib/libc/arch/i386/string/memset.S
+++ b/lib/libc/arch/i386/string/memset.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: memset.S,v 1.5 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: memset.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 ENTRY(memset)
 	pushl	%edi
@@ -53,4 +53,4 @@ L1:	rep
 	popl	%ebx
 	popl	%edi
 	ret
-END_STRONG(memset)
+END_BUILTIN(memset)
diff --git a/lib/libc/arch/i386/string/strchr.S b/lib/libc/arch/i386/string/strchr.S
index 3792d2292ab..a73f62311d9 100644
--- a/lib/libc/arch/i386/string/strchr.S
+++ b/lib/libc/arch/i386/string/strchr.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: strchr.S,v 1.7 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: strchr.S,v 1.8 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 WEAK_ALIAS(index, strchr)
 
diff --git a/lib/libc/arch/i386/string/strcmp.S b/lib/libc/arch/i386/string/strcmp.S
index 373232419e9..3bb042bd99f 100644
--- a/lib/libc/arch/i386/string/strcmp.S
+++ b/lib/libc/arch/i386/string/strcmp.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: strcmp.S,v 1.4 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: strcmp.S,v 1.5 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 /*
  * NOTE: I've unrolled the loop eight times: large enough to make a
diff --git a/lib/libc/arch/i386/string/strncmp.S b/lib/libc/arch/i386/string/strncmp.S
index bbe3f218a38..0d34a44d9fa 100644
--- a/lib/libc/arch/i386/string/strncmp.S
+++ b/lib/libc/arch/i386/string/strncmp.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: strncmp.S,v 1.5 2017/08/19 18:25:50 deraadt Exp $ */
+/*	$OpenBSD: strncmp.S,v 1.6 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 /*
  * NOTE: I've unrolled the loop eight times: large enough to make a
diff --git a/lib/libc/arch/i386/string/strrchr.S b/lib/libc/arch/i386/string/strrchr.S
index e1f5cc2e32e..24ce661ef25 100644
--- a/lib/libc/arch/i386/string/strrchr.S
+++ b/lib/libc/arch/i386/string/strrchr.S
@@ -1,10 +1,10 @@
-/*	$OpenBSD: strrchr.S,v 1.7 2015/08/31 02:53:56 guenther Exp $ */
+/*	$OpenBSD: strrchr.S,v 1.8 2017/11/29 05:13:57 guenther Exp $ */
 /*
  * Written by J.T. Conklin <jtc@netbsd.org>.
  * Public domain.
  */
 
-#include "SYS.h"
+#include "DEFS.h"
 
 WEAK_ALIAS(rindex, strrchr)
 
diff --git a/lib/libc/hidden/string.h b/lib/libc/hidden/string.h
index 0b9554a9f4a..a81cb0bf327 100644
--- a/lib/libc/hidden/string.h
+++ b/lib/libc/hidden/string.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: string.h,v 1.4 2017/09/05 03:16:13 schwarze Exp $	*/
+/*	$OpenBSD: string.h,v 1.5 2017/11/29 05:13:57 guenther Exp $	*/
 /*
  * Copyright (c) 2015 Philip Guenther <guenther@openbsd.org>
  *
@@ -33,11 +33,11 @@ PROTO_DEPRECATED(index);
 PROTO_NORMAL(memccpy);
 PROTO_NORMAL(memchr);
 PROTO_NORMAL(memcmp);
-PROTO_NORMAL(memcpy);
+/*PROTO_NORMAL(memcpy);			use declaration from namespace.h */
 PROTO_NORMAL(memmem);
-PROTO_NORMAL(memmove);
+/*PROTO_NORMAL(memmove);		use declaration from namespace.h */
 PROTO_NORMAL(memrchr);
-PROTO_NORMAL(memset);
+/*PROTO_NORMAL(memset);			use declaration from namespace.h */
 PROTO_DEPRECATED(rindex);
 PROTO_DEPRECATED(stpcpy);
 PROTO_NORMAL(stpncpy);
diff --git a/lib/libc/include/namespace.h b/lib/libc/include/namespace.h
index 980c1a8dd61..73b845e10f1 100644
--- a/lib/libc/include/namespace.h
+++ b/lib/libc/include/namespace.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: namespace.h,v 1.10 2016/05/07 19:05:22 guenther Exp $	*/
+/*	$OpenBSD: namespace.h,v 1.11 2017/11/29 05:13:57 guenther Exp $	*/
 
 #ifndef _LIBC_NAMESPACE_H_
 #define _LIBC_NAMESPACE_H_
@@ -154,23 +154,35 @@
 #define	DEF_CANCEL(x)		__weak_alias(x, CANCEL(x))
 #define	DEF_WRAP(x)		__weak_alias(x, WRAP(x))
 #define	DEF_SYS(x)		__strong_alias(_thread_sys_##x, HIDDEN(x))
+#ifdef __clang__
+#define	DEF_BUILTIN(x)		__asm("")
+#define	BUILTIN			__attribute__((__visibility__("protected")))
+#else
+#define	DEF_BUILTIN(x)		DEF_STRONG(x)
+#define	BUILTIN
+#endif
 
 #define	MAKE_CLONE(dst, src)	__dso_hidden typeof(dst) HIDDEN(dst) \
 				__attribute__((alias (HIDDEN_STRING(src))))
 
 
 /*
- * gcc will generate calls to the functions below.
+ * gcc and clang will generate calls to the functions below.
  * Declare and redirect them here so we always go
  * directly to our hidden aliases.
  */
 #include <sys/_types.h>
-void	*memcpy(void *__restrict, const void *__restrict, __size_t);
-void	*memset(void *, int, __size_t);
-void	__stack_smash_handler(const char [], int __attribute__((__unused__)));
+BUILTIN void	*memmove(void *, const void *, __size_t);
+BUILTIN void	*memcpy(void *__restrict, const void *__restrict, __size_t);
+BUILTIN void	*memset(void *, int, __size_t);
+BUILTIN void	__stack_smash_handler(const char [], int __unused);
+#ifndef __clang__
+PROTO_NORMAL(memmove);
 PROTO_NORMAL(memcpy);
 PROTO_NORMAL(memset);
 PROTO_NORMAL(__stack_smash_handler);
+#endif
+#undef	BUILTIN
 
 #endif  /* _LIBC_NAMESPACE_H_ */
 
diff --git a/lib/libc/string/memcpy.c b/lib/libc/string/memcpy.c
index a2516ed041a..19fddc0ab5f 100644
--- a/lib/libc/string/memcpy.c
+++ b/lib/libc/string/memcpy.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memcpy.c,v 1.3 2017/08/14 17:10:02 guenther Exp $ */
+/*	$OpenBSD: memcpy.c,v 1.4 2017/11/29 05:13:57 guenther Exp $ */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -106,4 +106,4 @@ memcpy(void *dst0, const void *src0, size_t length)
 done:
 	return (dst0);
 }
-DEF_STRONG(memcpy);
+DEF_BUILTIN(memcpy);
diff --git a/lib/libc/string/memmove.c b/lib/libc/string/memmove.c
index 2f1deb2c70d..1cd1086ab97 100644
--- a/lib/libc/string/memmove.c
+++ b/lib/libc/string/memmove.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memmove.c,v 1.2 2015/08/31 02:53:57 guenther Exp $ */
+/*	$OpenBSD: memmove.c,v 1.3 2017/11/29 05:13:57 guenther Exp $ */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -110,4 +110,4 @@ memmove(void *dst0, const void *src0, size_t length)
 done:
 	return (dst0);
 }
-DEF_STRONG(memmove);
+DEF_BUILTIN(memmove);
diff --git a/lib/libc/string/memset.c b/lib/libc/string/memset.c
index 242529ee0f2..0c261f0965a 100644
--- a/lib/libc/string/memset.c
+++ b/lib/libc/string/memset.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: memset.c,v 1.7 2015/08/31 02:53:57 guenther Exp $ */
+/*	$OpenBSD: memset.c,v 1.8 2017/11/29 05:13:57 guenther Exp $ */
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -45,4 +45,4 @@ memset(void *dst, int c, size_t n)
 	}
 	return (dst);
 }
-DEF_STRONG(memset);
+DEF_BUILTIN(memset);
diff --git a/lib/libc/sys/stack_protector.c b/lib/libc/sys/stack_protector.c
index 116aecd316a..d9ecb2cfbb4 100644
--- a/lib/libc/sys/stack_protector.c
+++ b/lib/libc/sys/stack_protector.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: stack_protector.c,v 1.23 2016/03/21 22:41:28 bluhm Exp $	*/
+/*	$OpenBSD: stack_protector.c,v 1.24 2017/11/29 05:13:57 guenther Exp $	*/
 
 /*
  * Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
@@ -80,4 +80,4 @@ __stack_smash_handler(const char func[], int damaged)
 
 	_exit(127);
 }
-DEF_STRONG(__stack_smash_handler);
+DEF_BUILTIN(__stack_smash_handler);