[COMMITTED PATCH] PLT avoidance for _exit in rtld.

[COMMITTED PATCH] PLT avoidance for _exit in rtld.

[Roland McGrath]

This saves 24 bytes of code on i686-linux-gnu, where calls the compiler
thinks will use the PLT (but actually won't at link time) require setting
up %ebx.  It has no effect at all on x86_64-linux-gnu (and probably most or
all other machines).


Thanks,
Roland


2015-07-09  Roland McGrath  <roland@hack.frob.com>

	* include/unistd.h: Add rtld_hidden_proto for _exit.
	* posix/_exit.c: Add rtld_hidden_def.
	* sysdeps/mach/hurd/_exit.c: Likewise.
	* sysdeps/nacl/_exit.c: Likewise.
	* sysdeps/unix/sysv/linux/_exit.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/_exit.S: Likewise.

diff --git a/include/unistd.h b/include/unistd.h
index 61df3af..fbba393 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -5,6 +5,7 @@
 __BEGIN_DECLS
 
 libc_hidden_proto (_exit, __noreturn__)
+rtld_hidden_proto (_exit, __noreturn__)
 libc_hidden_proto (alarm)
 libc_hidden_proto (confstr)
 libc_hidden_proto (execl)
diff --git a/posix/_exit.c b/posix/_exit.c
index ceff1a3..f4d76a1 100644
--- a/posix/_exit.c
+++ b/posix/_exit.c
@@ -29,6 +29,7 @@ _exit (status)
   abort ();
 }
 libc_hidden_def (_exit)
+rtld_hidden_def (_exit)
 weak_alias (_exit, _Exit)
 
 stub_warning (_exit)
diff --git a/sysdeps/mach/hurd/_exit.c b/sysdeps/mach/hurd/_exit.c
index 15c21fc..978b68f 100644
--- a/sysdeps/mach/hurd/_exit.c
+++ b/sysdeps/mach/hurd/_exit.c
@@ -52,4 +52,5 @@ _exit (status)
   _hurd_exit (W_EXITCODE (status, 0));
 }
 libc_hidden_def (_exit)
+rtld_hidden_def (_exit)
 weak_alias (_exit, _Exit)
diff --git a/sysdeps/nacl/_exit.c b/sysdeps/nacl/_exit.c
index 6006e26..b3b32ee 100644
--- a/sysdeps/nacl/_exit.c
+++ b/sysdeps/nacl/_exit.c
@@ -31,4 +31,5 @@ _exit (int status)
     __builtin_trap ();
 }
 libc_hidden_def (_exit)
+rtld_hidden_def (_exit)
 weak_alias (_exit, _Exit)
diff --git a/sysdeps/unix/sysv/linux/_exit.c b/sysdeps/unix/sysv/linux/_exit.c
index 7228181..2294c80 100644
--- a/sysdeps/unix/sysv/linux/_exit.c
+++ b/sysdeps/unix/sysv/linux/_exit.c
@@ -39,4 +39,5 @@ _exit (status)
     }
 }
 libc_hidden_def (_exit)
+rtld_hidden_def (_exit)
 weak_alias (_exit, _Exit)
diff --git a/sysdeps/unix/sysv/linux/i386/_exit.S b/sysdeps/unix/sysv/linux/i386/_exit.S
index 8841110..f470be8 100644
--- a/sysdeps/unix/sysv/linux/i386/_exit.S
+++ b/sysdeps/unix/sysv/linux/i386/_exit.S
@@ -40,4 +40,5 @@ _exit:
 	.size	_exit,.-_exit
 
 libc_hidden_def (_exit)
+rtld_hidden_def (_exit)
 weak_alias (_exit, _Exit)