hurd: keep only required PLTs in ld.so

We need NO_RTLD_HIDDEN because of the need for PLT calls in ld.so.
See Roland's comment in
https://sourceware.org/bugzilla/show_bug.cgi?id=15605
"in the Hurd it's crucial that calls like __mmap be the libc ones
instead of the rtld-local ones after the bootstrap phase, when the
dynamic linker is being used for dlopen and the like."

We used to just avoid all hidden use in the rtld ; this commit switches to
keeping only those that should use PLT calls, i.e. essentially those defined in
sysdeps/mach/hurd/dl-sysdep.c:

__assert_fail
__assert_perror_fail
__*stat64
_exit

This fixes a few startup issues, notably the call to __tunable_get_val that is
made before PLTs are set up.

4 files changed, 5 insertions, 17 deletions

diff --git a/sysdeps/mach/hurd/_exit.c b/sysdeps/mach/hurd/_exit.c
index 46db06db63..f04c5d2acf 100644
--- a/sysdeps/mach/hurd/_exit.c
+++ b/sysdeps/mach/hurd/_exit.c
@@ -51,5 +51,7 @@ _exit (int status)
   _hurd_exit (W_EXITCODE (status, 0));
 }
 libc_hidden_def (_exit)
+#ifndef NO_RTLD_HIDDEN
 rtld_hidden_def (_exit)
+#endif
 weak_alias (_exit, _Exit)
diff --git a/sysdeps/mach/hurd/dl-sysdep.c b/sysdeps/mach/hurd/dl-sysdep.c
index 5c0bb3124d..6b32d41c76 100644
--- a/sysdeps/mach/hurd/dl-sysdep.c
+++ b/sysdeps/mach/hurd/dl-sysdep.c
@@ -641,7 +641,8 @@ __sbrk (intptr_t increment)
   return (void *) addr;
 }
 
-check_no_hidden(__strtoul_internal);
+/* This is only used by hurdlookup for the /dev/fd/nnn magic.
+ * We avoid pulling the whole libc implementation, and we can keep this hidden.  */
 unsigned long int weak_function
 __strtoul_internal (const char *nptr, char **endptr, int base, int group)
 {
@@ -698,7 +699,6 @@ abort (void)
 /* We need this alias to satisfy references from libc_pic.a objects
    that were affected by the libc_hidden_proto declaration for abort.  */
 strong_alias (abort, __GI_abort)
-strong_alias (abort, __GI___chk_fail)
 strong_alias (abort, __GI___fortify_fail)
 strong_alias (abort, __GI___assert_fail)
 strong_alias (abort, __GI___assert_perror_fail)
diff --git a/sysdeps/mach/hurd/i386/ld.abilist b/sysdeps/mach/hurd/i386/ld.abilist
index 2e9bf2811f..0eaea9f66d 100644
--- a/sysdeps/mach/hurd/i386/ld.abilist
+++ b/sysdeps/mach/hurd/i386/ld.abilist
@@ -9,7 +9,6 @@ GLIBC_2.2.6 __open64 F
 GLIBC_2.2.6 __pread64 F
 GLIBC_2.2.6 __read F
 GLIBC_2.2.6 __sbrk F
-GLIBC_2.2.6 __strtoul_internal F
 GLIBC_2.2.6 __write F
 GLIBC_2.2.6 __writev F
 GLIBC_2.2.6 __xstat64 F
diff --git a/sysdeps/mach/hurd/i386/localplt.data b/sysdeps/mach/hurd/i386/localplt.data
index b199e14e7f..abd8f31fac 100644
--- a/sysdeps/mach/hurd/i386/localplt.data
+++ b/sysdeps/mach/hurd/i386/localplt.data
@@ -37,24 +37,11 @@ ld.so: __access_noerrno
 ld.so: __getpid
 ld.so: __getcwd
 ld.so: __sbrk
-ld.so: __strtoul_internal
-#ld.so: _exit
+ld.so: _exit ?
 ld.so: abort
 ld.so: _hurd_intr_rpc_mach_msg
 ld.so: __errno_location
-# rtld_hidden is currently disabled to avoid having to special-case the
-# functions above which do need a PLT.  These are thus currently expected.
-ld.so: _dl_allocate_tls
-ld.so: _dl_allocate_tls_init
-ld.so: _dl_exception_create
-ld.so: _dl_exception_create_format
-ld.so: _dl_exception_free
-ld.so: _dl_fatal_printf
-ld.so: _dl_find_dso_for_object
 ld.so: _dl_init_first
-ld.so: _dl_mcount
-ld.so: ___tls_get_addr
-ld.so: __tunable_get_val
 #
 # These should ideally be avoided, but is currently difficult
 libc.so: siglongjmp ?