Mark internal functions with attribute_hidden [BZ #18822]

Mark internal functions with attribute_hidden to allow direct access to
internal functions within libc.so and libc.a without using GOT nor PLT.

Size comparison of libc.so:

On x86-64:
        text	   data	    bss	    dec	    hex
Before: 1728577	  20584	  17088	1766249	 1af369
After : 1728593	  20584	  17088	1766265	 1af379

The only change is __gconv_release_shlib in iconv/gconv_dl.c is inlined
since it is hidden, which increases the code size of gconv_dl.os by 18
bytes.

On i686:
        text	   data	    bss	    dec	    hex
Before: 1869039	  11444	  11112	1891595	 1cdd0b
After : 1868635	  11444	  11112	1891191	 1cdb77

The code size is decreased by avoiding GOT/PLT for hidden functions.

	[BZ #18822]
	* iconv/gconv_int.h (__gconv_open): Add attribute_hidden.
	(__gconv_close): Likewise.
	(__gconv): Likewise.
	(__gconv_find_transform): Likewise.
	(__gconv_lookup_cache): Likewise.
	(__gconv_compare_alias_cache): Likewise.
	(__gconv_load_cache): Likewise.
	(__gconv_get_path): Likewise.
	(__gconv_close_transform): Likewise.
	(__gconv_release_cache): Likewise.
	(__gconv_find_shlib): Likewise.
	(__gconv_release_shlib): Likewise.
	(__gconv_get_builtin_trans): Likewise.
	(__gconv_compare_alias): Likewise.
	* include/dlfcn.h (_dlerror_run): Likewise.
	* include/stdio.h (__fortify_fail_abort): Likewise.
	* include/time.h (__tz_compute): Likewise.
	(__strptime_internal): Likewise.
	* intl/gettextP.h (_nl_find_domain): Likewise.
	(_nl_load_domain): Likewise.
	(_nl_find_msg): Likewise.
	* intl/plural-exp.h (FREE_EXPRESSION): Likewise.
	(EXTRACT_PLURAL_EXPRESSION): Likewise.
	* locale/coll-lookup.h (__collidx_table_lookup): Likewise.
	* resolv/gai_misc.h (__gai_enqueue_request): Likewise.
	(__gai_find_request): Likewise.
	(__gai_remove_request): Likewise.
	(__gai_notify): Likewise.
	(__gai_notify_only): Likewise.
	* sysdeps/generic/aio_misc.h (__aio_sigqueue): Likewise.
	* sysdeps/generic/ldsodefs.h (_dl_fini): Likewise.
	(_dl_non_dynamic_init): Likewise.
	(_dl_aux_init): Likewise.
	* sysdeps/i386/machine-gmon.h (mcount_internal): Likewise.
	* sysdeps/unix/sysv/linux/i386/olddirent.h (__old_getdents64):
	Likewise.
	* wcsmbs/wcsmbsload.h (__wcsmbs_load_conv): Likewise.
	(__wcsmbs_clone_conv): Likewise.
	(__wcsmbs_named_conv): Likewise.

4 files changed, 10 insertions, 6 deletions

diff --git a/sysdeps/generic/aio_misc.h b/sysdeps/generic/aio_misc.h
index c0622b2ab6..d5a0297673 100644
--- a/sysdeps/generic/aio_misc.h
+++ b/sysdeps/generic/aio_misc.h
@@ -40,7 +40,8 @@ typedef union
 
 
 /* Send the signal.  */
-extern int __aio_sigqueue (int sig, const union sigval val, pid_t caller_pid);
+extern int __aio_sigqueue (int sig, const union sigval val, pid_t caller_pid)
+     attribute_hidden;
 
 
 #endif /* aio_misc.h */
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 1a4449eeb3..5efae2d96d 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -954,7 +954,7 @@ extern void _dl_init (struct link_map *main_map, int argc, char **argv,
 
 /* Call the finalizer functions of all shared objects whose
    initializer functions have completed.  */
-extern void _dl_fini (void);
+extern void _dl_fini (void) attribute_hidden;
 
 /* Sort array MAPS according to dependencies of the contained objects.  */
 extern void _dl_sort_fini (struct link_map **maps, size_t nmaps, char *used,
@@ -1123,10 +1123,12 @@ extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
 rtld_hidden_proto (_dl_find_dso_for_object)
 
 /* Initialization which is normally done by the dynamic linker.  */
-extern void _dl_non_dynamic_init (void);
+extern void _dl_non_dynamic_init (void)
+     attribute_hidden;
 
 /* Used by static binaries to check the auxiliary vector.  */
-extern void _dl_aux_init (ElfW(auxv_t) *av);
+extern void _dl_aux_init (ElfW(auxv_t) *av)
+     attribute_hidden;
 
 
 __END_DECLS
diff --git a/sysdeps/i386/machine-gmon.h b/sysdeps/i386/machine-gmon.h
index 3e90b8c0c7..81e168e4e6 100644
--- a/sysdeps/i386/machine-gmon.h
+++ b/sysdeps/i386/machine-gmon.h
@@ -30,7 +30,7 @@
 #define mcount_internal __mcount_internal
 
 extern void mcount_internal (u_long frompc, u_long selfpc)
-  __attribute__ ((regparm (2)));
+  __attribute__ ((regparm (2))) attribute_hidden;
 
 #define _MCOUNT_DECL(frompc, selfpc)                \
   __attribute__ ((regparm (2)))			    \
diff --git a/sysdeps/unix/sysv/linux/olddirent.h b/sysdeps/unix/sysv/linux/olddirent.h
index 0b4c81da0e..5510ab2095 100644
--- a/sysdeps/unix/sysv/linux/olddirent.h
+++ b/sysdeps/unix/sysv/linux/olddirent.h
@@ -34,7 +34,8 @@ extern struct __old_dirent64 *__old_readdir64 (DIR *__dirp);
 libc_hidden_proto (__old_readdir64);
 extern int __old_readdir64_r (DIR *__dirp, struct __old_dirent64 *__entry,
 			  struct __old_dirent64 **__result);
-extern __ssize_t __old_getdents64 (int __fd, char *__buf, size_t __nbytes);
+extern __ssize_t __old_getdents64 (int __fd, char *__buf, size_t __nbytes)
+	attribute_hidden;
 int __old_scandir64 (const char * __dir,
 		     struct __old_dirent64 *** __namelist,
 		     int (*__selector) (const struct __old_dirent64 *),