Support creating shared libraries on Hurd/x86_64.

Patch from
<https://lists.gnu.org/archive/html/bug-hurd/2023-05/msg00086.html>.

* m4/libtool.m4 (_LT_ENABLE_LOCK): Treat Hurd/x86_64 like
Linux/x86_64.

Author: bhaible

ChangeLog

@@ -1,3 +1,11 @@
+2023-05-21  Bruno Haible  <bruno@clisp.org>
+
+	Support creating shared libraries on Hurd/x86_64.
+	Patch from
+	<https://lists.gnu.org/archive/html/bug-hurd/2023-05/msg00086.html>.
+	* m4/libtool.m4 (_LT_ENABLE_LOCK): Treat Hurd/x86_64 like
+	Linux/x86_64.
+
 2023-05-21  Bruno Haible  <bruno@clisp.org>
 
 	Fix link error regarding _libiconv_version on MSVC in C++ mode.

libcharset/ChangeLog

@@ -1,3 +1,11 @@
+2023-05-21  Bruno Haible  <bruno@clisp.org>
+
+	Support creating shared libraries on Hurd/x86_64.
+	Patch from
+	<https://lists.gnu.org/archive/html/bug-hurd/2023-05/msg00086.html>.
+	* m4/libtool.m4 (_LT_ENABLE_LOCK): Treat Hurd/x86_64 like
+	Linux/x86_64.
+
 2022-07-17  Bruno Haible  <bruno@clisp.org>
 
 	Split autogen.sh into autopull.sh and autogen.sh.

libcharset/m4/libtool.m4

@@ -1,6 +1,6 @@
 # libtool.m4 - Configure libtool for the host system. -*-Autoconf-*-
 #
-#   Copyright (C) 1996-2001, 2003-2019, 2021-2022 Free Software
+#   Copyright (C) 1996-2001, 2003-2019, 2021-2023 Free Software
 #   Foundation, Inc.
 #   Written by Gordon Matzigkeit, 1996
 #
@@ -1368,7 +1368,7 @@ mips64*-*linux*)
   ;;
 
 x86_64-*kfreebsd*-gnu|x86_64-*linux*|powerpc*-*linux*| \
-s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
+s390*-*linux*|s390*-*tpf*|sparc*-*linux*|x86_64-gnu*)
   # Find out what ABI is being produced by ac_compile, and set linker
   # options accordingly.  Note that the listed cases only cover the
   # situations where additional linker options are needed (such as when
@@ -1383,7 +1383,7 @@ s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
-	  x86_64-*linux*)
+	  x86_64-*linux*|x86_64-gnu*)
 	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
@@ -1412,7 +1412,7 @@ s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_x86_64_fbsd"
 	    ;;
-	  x86_64-*linux*)
+	  x86_64-*linux*|x86_64-gnu*)
 	    LD="${LD-ld} -m elf_x86_64"
 	    ;;
 	  powerpcle-*linux*)

m4/libtool.m4

@@ -1,6 +1,6 @@
 # libtool.m4 - Configure libtool for the host system. -*-Autoconf-*-
 #
-#   Copyright (C) 1996-2001, 2003-2019, 2021-2022 Free Software
+#   Copyright (C) 1996-2001, 2003-2019, 2021-2023 Free Software
 #   Foundation, Inc.
 #   Written by Gordon Matzigkeit, 1996
 #
@@ -1368,7 +1368,7 @@ mips64*-*linux*)
   ;;
 
 x86_64-*kfreebsd*-gnu|x86_64-*linux*|powerpc*-*linux*| \
-s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
+s390*-*linux*|s390*-*tpf*|sparc*-*linux*|x86_64-gnu*)
   # Find out what ABI is being produced by ac_compile, and set linker
   # options accordingly.  Note that the listed cases only cover the
   # situations where additional linker options are needed (such as when
@@ -1383,7 +1383,7 @@ s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
-	  x86_64-*linux*)
+	  x86_64-*linux*|x86_64-gnu*)
 	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
@@ -1412,7 +1412,7 @@ s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_x86_64_fbsd"
 	    ;;
-	  x86_64-*linux*)
+	  x86_64-*linux*|x86_64-gnu*)
 	    LD="${LD-ld} -m elf_x86_64"
 	    ;;
 	  powerpcle-*linux*)