Re: [PATCH 1/3] Mark ld.so internel mmap functions hidden

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Mon, Oct 19, 2015 at 11:31 AM, Roland McGrath <roland@hack.frob.com> wrote:
> NAK to #ifdef in generic code.

Here is the updated patch with a new header file, dl-mman.h.
OK for master?

-- 
H.J.

From d35367c4ac22d9873f9643018be0326b31bc2987 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Wed, 14 Oct 2015 15:14:15 -0700
Subject: [PATCH 1/2] Mark ld.so internel mmap functions hidden

Since ld.so internel mmap functions are only used internally in ld.so,
they can be made hidden.  Don't hide __mmap on Hurd, since __mmap in
ld.so will be preempted by the one in libc.so after bootstrap.

	 [BZ #19122]
	 * include/sys/mman.h [IS_IN (rtld)]: Include <dl-mman.h>.
	 [IS_IN (rtld)] (__mprotect): Add attribute_hidden.
	 [IS_IN (rtld)] (__munmap): Likewise.
	 * sysdeps/generic/dl-mman.h: New file.
	 * sysdeps/mach/hurd/dl-mman.h: Likewise.
---
 include/sys/mman.h          |  6 ++++++
 sysdeps/generic/dl-mman.h   | 18 ++++++++++++++++++
 sysdeps/mach/hurd/dl-mman.h | 19 +++++++++++++++++++
 3 files changed, 43 insertions(+)
 create mode 100644 sysdeps/generic/dl-mman.h
 create mode 100644 sysdeps/mach/hurd/dl-mman.h

diff --git a/include/sys/mman.h b/include/sys/mman.h
index fd125ec..e112591 100644
--- a/include/sys/mman.h
+++ b/include/sys/mman.h
@@ -16,6 +16,12 @@ libc_hidden_proto (__madvise)
 /* This one is Linux specific.  */
 extern void *__mremap (void *__addr, size_t __old_len,
 		       size_t __new_len, int __flags, ...);
+
+# if IS_IN (rtld)
+#  include <dl-mman.h>
+extern __typeof (__mprotect) __mprotect attribute_hidden;
+extern __typeof (__munmap) __munmap attribute_hidden;
+# endif
 #endif
 
 #endif
diff --git a/sysdeps/generic/dl-mman.h b/sysdeps/generic/dl-mman.h
new file mode 100644
index 0000000..5b44d3a
--- /dev/null
+++ b/sysdeps/generic/dl-mman.h
@@ -0,0 +1,18 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+extern __typeof (__mmap) __mmap attribute_hidden;
diff --git a/sysdeps/mach/hurd/dl-mman.h b/sysdeps/mach/hurd/dl-mman.h
new file mode 100644
index 0000000..8821da5
--- /dev/null
+++ b/sysdeps/mach/hurd/dl-mman.h
@@ -0,0 +1,19 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Can't hide __mmap on Hurd, since __mmap in ld.so will be preempted by
+   the one in libc.so after bootstrap.  */
-- 
2.4.3