From bc8bb57301186279c74b55cd2daec9131d087ef8 Mon Sep 17 00:00:00 2001
From: guenther <>
Date: Wed, 29 Nov 2017 05:13:57 +0000
Subject: 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@
---
src/lib/libc/include/namespace.h | 22 +++++++++++++++++-----
src/lib/libc/string/memcpy.c | 4 ++--
src/lib/libc/string/memmove.c | 4 ++--
src/lib/libc/string/memset.c | 4 ++--
4 files changed, 23 insertions(+), 11 deletions(-)
(limited to 'src')
diff --git a/src/lib/libc/include/namespace.h b/src/lib/libc/include/namespace.h
index 980c1a8dd6..73b845e10f 100644
--- a/src/lib/libc/include/namespace.h
+++ b/src/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/src/lib/libc/string/memcpy.c b/src/lib/libc/string/memcpy.c
index a2516ed041..19fddc0ab5 100644
--- a/src/lib/libc/string/memcpy.c
+++ b/src/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/src/lib/libc/string/memmove.c b/src/lib/libc/string/memmove.c
index 2f1deb2c70..1cd1086ab9 100644
--- a/src/lib/libc/string/memmove.c
+++ b/src/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/src/lib/libc/string/memset.c b/src/lib/libc/string/memset.c
index 242529ee0f..0c261f0965 100644
--- a/src/lib/libc/string/memset.c
+++ b/src/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);
--
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