From 8bcdb7e0c5346d2e9d61b208d80fd8213e1dbd90 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sun, 1 Oct 2017 15:07:06 -0700
Subject: 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.
---
 include/dlfcn.h | 3 ++-
 include/stdio.h | 2 +-
 include/time.h  | 4 ++--
 3 files changed, 5 insertions(+), 4 deletions(-)

(limited to 'include')

diff --git a/include/dlfcn.h b/include/dlfcn.h
index 888e84d..526086f 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -72,7 +72,8 @@ extern void *_dl_vsym (void *handle, const char *name, const char *version,
    _dl_catch_error.  Returns zero for success, nonzero for failure; and
    arranges for `dlerror' to return the error details.
    ARGS is passed as argument to OPERATE.  */
-extern int _dlerror_run (void (*operate) (void *), void *args);
+extern int _dlerror_run (void (*operate) (void *), void *args)
+    attribute_hidden;
 
 #ifdef SHARED
 # define DL_CALLER_DECL /* Nothing */
diff --git a/include/stdio.h b/include/stdio.h
index 87e0e10..7625a2a 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -100,7 +100,7 @@ extern void __libc_message (enum __libc_message_action action,
 			    const char *__fnt, ...);
 extern void __fortify_fail (const char *msg) __attribute__ ((__noreturn__));
 extern void __fortify_fail_abort (_Bool, const char *msg)
-  __attribute__ ((__noreturn__));
+  __attribute__ ((__noreturn__)) attribute_hidden;
 libc_hidden_proto (__fortify_fail)
 libc_hidden_proto (__fortify_fail_abort)
 
diff --git a/include/time.h b/include/time.h
index 870b7eb..e8c07bb 100644
--- a/include/time.h
+++ b/include/time.h
@@ -46,7 +46,7 @@ extern void __tzfile_default (const char *std, const char *dst,
 			      long int stdoff, long int dstoff);
 extern void __tzset_parse_tz (const char *tz);
 extern void __tz_compute (time_t timer, struct tm *tm, int use_localtime)
-  __THROW;
+  __THROW attribute_hidden;
 
 /* Subroutine of `mktime'.  Return the `time_t' representation of TP and
    normalize TP, given that a `struct tm *' maps to a `time_t' as performed
@@ -89,7 +89,7 @@ extern int __getclktck (void);
 /* strptime support.  */
 extern char * __strptime_internal (const char *rp, const char *fmt,
 				   struct tm *tm, void *statep,
-				   locale_t locparam);
+				   locale_t locparam) attribute_hidden;
 
 extern double __difftime (time_t time1, time_t time0);
 
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