[PATCH] Use rcrt1.o%s/grcrt1.o%s to relocate static PIE

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Wed, Nov 1, 2017 at 9:39 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Wed, Nov 1, 2017 at 9:32 AM, Rich Felker <dalias@libc.org> wrote:
>> On Sun, Oct 15, 2017 at 06:16:57AM -0700, H.J. Lu wrote:
>>> crt1.o is used to create dynamic and non-PIE static executables.  Static
>>> PIE needs to link with Pcrt1.o, instead of crt1.o, to relocate static PIE
>>> at run-time.  When -pg is used with -static-pie, gPcrt1.o should be used.
>>>
>>> Tested on x86-64.  OK for master?
>>
>> Is there a reason you didn't follow the existing naming practice here?
>> Openbsd and musl libc have both had static pie for a long time now and
>> have used rcrt1.o as the name.
>
> I wasn't aware of rcrt1.o and there is no reference to rcrt1.o in GCC at all.
> Does the FSF GCC support static PIE for musl libc? If not, is there a GCC
> bug for it?
>
> BTW, I don't mind replacing Pcrt1.o/gPcrt1.o with rcrt1.o/grcrt1.o.
>

Here is the updated patch to use rcrt1.o/grcrt1.o.

OK for trunk?

Thanks.


-- 
H.J.

From 4d727ac09ef22d0706b30055a233920ffa2419a8 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 3 Oct 2017 17:29:13 -0700
Subject: [PATCH] Use rcrt1.o%s/grcrt1.o%s to relocate static PIE

crt1.o is used to create dynamic and non-PIE static executables.  Static
PIE needs to link with rcrt1.o, instead of crt1.o, which is also used by
musl libc and OpenBSD:

https://gcc.gnu.org/ml/gcc/2015-06/msg00008.html

to relocate static PIE at run-time.  When -pg is used with -static-pie,
grcrt1.o should be used.

	* config/gnu-user.h (GNU_USER_TARGET_STARTFILE_SPEC): Use
	rcrt1.o%s/grcrt1.o%s for -static-pie.
---
 gcc/config/gnu-user.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/gcc/config/gnu-user.h b/gcc/config/gnu-user.h
index df17b180906..93960f5cacb 100644
--- a/gcc/config/gnu-user.h
+++ b/gcc/config/gnu-user.h
@@ -51,9 +51,10 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #if defined HAVE_LD_PIE
 #define GNU_USER_TARGET_STARTFILE_SPEC \
   "%{shared:; \
-     pg|p|profile:gcrt1.o%s; \
+     pg|p|profile:%{static-pie:grcrt1.o%s;:gcrt1.o%s}; \
      static:crt1.o%s; \
-     static-pie|" PIE_SPEC ":Scrt1.o%s; \
+     static-pie:rcrt1.o%s; \
+     " PIE_SPEC ":Scrt1.o%s; \
      :crt1.o%s} \
    crti.o%s \
    %{static:crtbeginT.o%s; \
-- 
2.13.6