ld: Add --export-dynamic-symbol and --export-dynamic-symbol-list

--export-dynamic-symbol-list is like a dynamic list, but without
the symbolic property for unspecified symbols.

When creating an executable, --export-dynamic-symbol-list is treated
like --dynamic-list.

When creating a shared library, it is treated like --dynamic-list if
-Bsymbolic or --dynamic-list are used,  otherwise, it is ignored, so
that references to matched symbols will not be bound to the definitions
within the shared library.

	PR ld/25910
	* NEWS: Mention --export-dynamic-symbol[-list].
	* ld.texi: Document --export-dynamic-symbol[-list].
	* ldgram.y: Pass current_dynamic_list_p to
	lang_append_dynamic_list.
	* ldlang.c (current_dynamic_list_p): New.
	(ang_append_dynamic_list): Updated to take a pointer to
	struct bfd_elf_dynamic_list * argument instead of using
	link_info.dynamic_list.
	(lang_append_dynamic_list_cpp_typeinfo): Pass
	&link_info.dynamic_list to ang_append_dynamic_list.
	(lang_append_dynamic_list_cpp_new): Likewise.
	* ldlang.h (current_dynamic_list_p): New.
	(lang_append_dynamic_list): Add a pointer to
	struct bfd_elf_dynamic_list * argument.
	* ldlex.h (option_values): Add OPTION_EXPORT_DYNAMIC_SYMBOL and
	OPTION_EXPORT_DYNAMIC_SYMBOL_LIST.
	* lexsup.c (ld_options): Add entries for
	OPTION_EXPORT_DYNAMIC_SYMBOL and
	OPTION_EXPORT_DYNAMIC_SYMBOL_LIST.
	(parse_args): Handle --export-dynamic-symbol and
	--export-dynamic-symbol-list.
	* testsuite/ld-dynamic/export-dynamic-symbol-1.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol-2.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol-glob.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol-list-1.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol-list-2.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol-list-glob.d: New.
	* testsuite/ld-dynamic/export-dynamic-symbol.exp: New.
	* testsuite/ld-dynamic/export-dynamic-symbol.s: New.
	* testsuite/ld-dynamic/foo-bar.list: New.
	* testsuite/ld-dynamic/foo.list: New.
	* testsuite/ld-dynamic/foo.s: New.
	* testsuite/ld-dynamic/fstar.list: New.
	* testsuite/ld-elf/dlempty.list: New.
	* testsuite/ld-elf/shared.exp: Add tests for
	--export-dynamic-symbol and --export-dynamic-symbol-list.

12 files changed, 146 insertions, 0 deletions

diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-1.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-1.d
new file mode 100644
index 0000000..25ae130
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-1.d
@@ -0,0 +1,9 @@
+#name: --export-dynamic-symbol foo archive
+#source: export-dynamic-symbol.s
+#ld: -pie --export-dynamic-symbol foo tmpdir/libpr25910.a
+#nm: -n
+
+#failif
+#...
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-2.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-2.d
new file mode 100644
index 0000000..d38508a
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-2.d
@@ -0,0 +1,9 @@
+#name: -u --export-dynamic-symbol foo archive
+#source: export-dynamic-symbol.s
+#ld: -pie -u foo --export-dynamic-symbol foo --export-dynamic-symbol=bar tmpdir/libpr25910.a
+#nm: -D
+
+#...
+[0-9a-f]+ T +bar
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-glob.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-glob.d
new file mode 100644
index 0000000..f8187be
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-glob.d
@@ -0,0 +1,8 @@
+#name: -u --export-dynamic-symbol "f*" archive
+#source: export-dynamic-symbol.s
+#ld: -pie -u foo --export-dynamic-symbol "f*" tmpdir/libpr25910.a
+#nm: -D
+
+#...
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-1.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-1.d
new file mode 100644
index 0000000..fc58af9
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-1.d
@@ -0,0 +1,9 @@
+#name: --export-dynamic-symbol-list foo archive
+#source: export-dynamic-symbol.s
+#ld: -pie --export-dynamic-symbol-list foo.list tmpdir/libpr25910.a
+#nm: -n
+
+#failif
+#...
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-2.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-2.d
new file mode 100644
index 0000000..337f642
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-2.d
@@ -0,0 +1,9 @@
+#name: -u --export-dynamic-symbol-list foo bar archive
+#source: export-dynamic-symbol.s
+#ld: -pie -u foo --export-dynamic-symbol-list foo-bar.list tmpdir/libpr25910.a
+#nm: -D
+
+#...
+[0-9a-f]+ T +bar
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-glob.d b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-glob.d
new file mode 100644
index 0000000..916a22c
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol-list-glob.d
@@ -0,0 +1,8 @@
+#name: -u --export-dynamic-symbol-list fstar archive
+#source: export-dynamic-symbol.s
+#ld: -pie -u foo --export-dynamic-symbol-list fstar.list tmpdir/libpr25910.a
+#nm: -D
+
+#...
+[0-9a-f]+ T +foo
+#...
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol.exp b/ld/testsuite/ld-dynamic/export-dynamic-symbol.exp
new file mode 100644
index 0000000..ae53036
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol.exp
@@ -0,0 +1,70 @@
+# Expect script for ld --export-dynamic-symbol tests
+#   Copyright (C) 2020 Free Software Foundation, Inc.
+#
+# This file is part of the GNU Binutils.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+#
+
+if ![is_elf_format] {
+    return
+}
+
+# Skip targets where -shared is not supported
+
+if ![check_shared_lib_support] {
+    return
+}
+
+set old_ASFLAGS $ASFLAGS
+
+# These targets require extra GAS options when building code for shared
+# libraries.
+if [istarget "nds32*-*"] {
+    append ASFLAGS " -mpic"
+}
+if [istarget "tic6x-*-*"] {
+    append ASFLAGS " -mpic -mpid=near"
+}
+if [istarget "sparc*-*-*"] {
+    append ASFLAGS " -K PIC -Av9"
+}
+
+set old_LDFLAGS $LDFLAGS
+
+# These targets require a non-default emulation for successful shared
+# library/executable builds.
+if [istarget "tic6x-*-*"] {
+    append LDFLAGS " -melf32_tic6x_le"
+}
+
+set build_tests {
+  {"Build libpr25910.a"
+   "" "" ""
+   {foo.s} {} "libpr25910.a"}
+}
+
+run_ld_link_tests $build_tests
+
+set test_list [lsort [glob -nocomplain $srcdir/$subdir/export-dynamic-symbol-*.d]]
+foreach test_file $test_list {
+    set test_name [file rootname $test_file]
+    verbose $test_name
+    run_dump_test $test_name
+}
+
+set ASFLAGS $old_ASFLAGS
+set LDFLAGS $old_LDFLAGS
diff --git a/ld/testsuite/ld-dynamic/export-dynamic-symbol.s b/ld/testsuite/ld-dynamic/export-dynamic-symbol.s
new file mode 100644
index 0000000..c55da53
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/export-dynamic-symbol.s
@@ -0,0 +1,17 @@
+	.text
+	.global start	/* Used by SH targets.  */
+start:
+	.global _start
+_start:
+	.global __start
+__start:
+	.global main	/* Used by HPPA targets.  */
+main:
+	.globl	_main	/* Used by LynxOS targets.  */
+_main:
+	.word 0
+
+	.section .text.1, "ax"
+	.global bar
+bar:
+	.word 0
diff --git a/ld/testsuite/ld-dynamic/foo-bar.list b/ld/testsuite/ld-dynamic/foo-bar.list
new file mode 100644
index 0000000..87732e1
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/foo-bar.list
@@ -0,0 +1 @@
+{ foo; bar; };
diff --git a/ld/testsuite/ld-dynamic/foo.list b/ld/testsuite/ld-dynamic/foo.list
new file mode 100644
index 0000000..f89f569
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/foo.list
@@ -0,0 +1 @@
+{ foo; };
diff --git a/ld/testsuite/ld-dynamic/foo.s b/ld/testsuite/ld-dynamic/foo.s
new file mode 100644
index 0000000..4a70181
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/foo.s
@@ -0,0 +1,4 @@
+	.text
+	.globl foo
+foo:
+	.byte 0
diff --git a/ld/testsuite/ld-dynamic/fstar.list b/ld/testsuite/ld-dynamic/fstar.list
new file mode 100644
index 0000000..330d1dd
--- /dev/null
+++ b/ld/testsuite/ld-dynamic/fstar.list
@@ -0,0 +1 @@
+{ f*; };