From 0bfad4329818423960a75ed0a305005098e237ac Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Thu, 16 Jul 2020 21:58:43 +0000
Subject: [PATCH] Include ABI note tag in shared libraries.

Split the ELF feature note into a separate file that is linked into
*crt1.o the same as crtbrand.S was before.  crtbrand.o is now linked
into crti.o on all platforms in addition to *crt1.o.

Reviewed by:	kib
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D25304
---
 lib/csu/Makefile.inc          |  9 +++++++-
 lib/csu/common/crtbrand.S     | 12 +---------
 lib/csu/common/feature_note.S | 42 +++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 12 deletions(-)
 create mode 100644 lib/csu/common/feature_note.S

diff --git a/lib/csu/Makefile.inc b/lib/csu/Makefile.inc
index 319f7075093..5681ef65117 100644
--- a/lib/csu/Makefile.inc
+++ b/lib/csu/Makefile.inc
@@ -13,7 +13,7 @@ OBJS+=	crtbegin.o crtbeginS.o crtbeginT.o
 OBJS+=	crtend.o crtendS.o
 OBJS+=	crti.o crtn.o
 
-CRT1OBJS+=	crtbrand.o ignore_init_note.o
+CRT1OBJS+=	crtbrand.o feature_note.o ignore_init_note.o
 
 ACFLAGS+=	-DLOCORE
 
@@ -33,6 +33,7 @@ FILESDIR=	${LIBDIR}
 .undef LIBRARIES_ONLY
 
 CLEANFILES+=	${OBJS} ${CRT1OBJS} crt1_c.o gcrt1_c.o Scrt1_c.o
+CLEANFILES+=	crti_s.o
 
 crt1.o:	crt1_c.o ${CRT1OBJS}
 	${LD} ${_LDFLAGS} -o ${.TARGET} -r ${.ALLSRC:M*.o}
@@ -68,6 +69,12 @@ crtbeginS.o crtendS.o:
 	${CC} ${CFLAGS} -I${.CURDIR} ${CFLAGS_CRTS} -c -o ${.TARGET} \
 	    ${.ALLSRC:N*.h:[1]}
 
+crti_s.o: crti.S
+	${CC} ${CFLAGS} ${ACFLAGS} -c ${.ALLSRC:M*.S} -o ${.TARGET}
+
+crti.o: crti_s.o crtbrand.o
+	${LD} ${_LDFLAGS} -o ${.TARGET} -r ${.ALLSRC:M*.o}
+
 .endif
 
 .include "../Makefile.inc"
diff --git a/lib/csu/common/crtbrand.S b/lib/csu/common/crtbrand.S
index 8efe7fb6347..bf223d84bc1 100644
--- a/lib/csu/common/crtbrand.S
+++ b/lib/csu/common/crtbrand.S
@@ -38,7 +38,7 @@ __FBSDID("$FreeBSD$");
  * for more information.
  */
 
-	.section .note.tag,"a",%note
+	.section .note.tag,"aG",%note,.freebsd.noteG,comdat
 	.p2align	2
 	.4byte		2f-1f
 	.4byte		4f-3f
@@ -46,14 +46,4 @@ __FBSDID("$FreeBSD$");
 1:	.asciz		NOTE_FREEBSD_VENDOR
 2:	.p2align	2
 3:	.4byte		__FreeBSD_version
-4:
-
-	.section .note.tag,"a",%note
-	.p2align	2
-	.4byte		2f-1f
-	.4byte		4f-3f
-	.4byte		NT_FREEBSD_FEATURE_CTL
-1:	.asciz		NOTE_FREEBSD_VENDOR
-2:	.p2align	2
-3:	.4byte		0
 4:
diff --git a/lib/csu/common/feature_note.S b/lib/csu/common/feature_note.S
new file mode 100644
index 00000000000..0274ce61deb
--- /dev/null
+++ b/lib/csu/common/feature_note.S
@@ -0,0 +1,42 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright 2000 David E. O'Brien, John D. Polstra.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <machine/asm.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/elf_common.h>
+#include "notes.h"
+
+	.section .note.tag,"a",%note
+	.p2align	2
+	.4byte		2f-1f
+	.4byte		4f-3f
+	.4byte		NT_FREEBSD_FEATURE_CTL
+1:	.asciz		NOTE_FREEBSD_VENDOR
+2:	.p2align	2
+3:	.4byte		0
+4:
-- 
2.45.0