Fix sem_* tdelete, tfind, tsearch, twalk namespace (bug 18536).

The sem_* functions bring in references to tdelete, tfind, tsearch and
twalk.  But the t* functions are XSI-shaded, while sem_* aren't.  This
patch fixes this by using __t* instead, exporting those functions from
libc at version GLIBC_PRIVATE (since sem_* are in libpthread) and
using libc_hidden_* for the benefit of calls within libc.

Tested for x86_64 and x86 (testsuite, and comparison of disassembly of
installed stripped shared libraries).  libpthread gets changes from
PLT reordering; addresses in libc change because of PLT / dynamic
symbol table changes.

	[BZ #18536]
	* misc/tsearch.c (__tsearch): Use libc_hidden_def.
	(__tfind): Likewise.
	(__tdelete): Likewise.
	(__twalk): Likewise.
	* misc/Versions (libc): Add __tdelete, __tfind, __tsearch and
	__twalk to GLIBC_PRIVATE.
	* include/search.h (__tsearch): Use libc_hidden_proto.
	(__tfind): Likewise.
	(__tdelete): Likewise.
	(__twalk): Likewise.
	* nptl/sem_close.c (sem_close): Call __twalk instead of twalk.
	Call __tdelete instead of tdelete.
	* nptl/sem_open.c (check_add_mapping): Call __tfind instead of
	tfind.  Call __tsearch instead of tsearch.
	* sysdeps/sparc/sparc32/sem_open.c (check_add_mapping): Likewise.
	* conform/Makefile (test-xfail-POSIX/semaphore.h/linknamespace):
	Remove variable.
	(test-xfail-POSIX2008/semaphore.h/linknamespace): Likewise.

2 files changed, 5 insertions, 0 deletions

diff --git a/misc/Versions b/misc/Versions
index ec5aea7b52..534d1a3fca 100644
--- a/misc/Versions
+++ b/misc/Versions
@@ -153,5 +153,6 @@ libc {
     __madvise;
     __mktemp;
     __libc_ifunc_impl_list;
+    __tdelete; __tfind; __tsearch; __twalk;
   }
 }
diff --git a/misc/tsearch.c b/misc/tsearch.c
index d4052e8397..869dc9bec7 100644
--- a/misc/tsearch.c
+++ b/misc/tsearch.c
@@ -293,6 +293,7 @@ __tsearch (const void *key, void **vrootp, __compar_fn_t compar)
 
   return q;
 }
+libc_hidden_def (__tsearch)
 weak_alias (__tsearch, tsearch)
 
 
@@ -325,6 +326,7 @@ __tfind (key, vrootp, compar)
     }
   return NULL;
 }
+libc_hidden_def (__tfind)
 weak_alias (__tfind, tfind)
 
 
@@ -585,6 +587,7 @@ __tdelete (const void *key, void **vrootp, __compar_fn_t compar)
   free (unchained);
   return retval;
 }
+libc_hidden_def (__tdelete)
 weak_alias (__tdelete, tdelete)
 
 
@@ -625,6 +628,7 @@ __twalk (const void *vroot, __action_fn_t action)
   if (root != NULL && action != NULL)
     trecurse (root, action, 0);
 }
+libc_hidden_def (__twalk)
 weak_alias (__twalk, twalk)