I wrote:
> * modules/qcopy-acl (Depends-on): Add condition.
> (configure.ac): Set QCOPY_ACL_LIB.
> (Link): Add $(QCOPY_ACL_LIB). Remove $(LIB_ACL).
Oops, this has a mistake. The variable LIB_ACL needs to be initialized
before the code uses its value; otherwise $LIB_ACL will come out as empty.
The way to order the initialization is to use AC_REQUIRE of the macro
which defines LIB_ACL. Then, since invocation and AC_REQUIRE of a macro
defined through AC_DEFUN triggers an autoconf warning, one needs AC_DEFUN_ONCE
instead.
2023-01-13 Bruno Haible <br...@clisp.org>
qcopy-acl: Make last patch more robust.
* m4/acl.m4 (gl_FUNC_ACL): Define through AC_DEFUN_ONCE.
* modules/qcopy-acl (configure.ac): Require gl_FUNC_ACL.
diff --git a/m4/acl.m4 b/m4/acl.m4
index e612f1ae34..dc9853a156 100644
--- a/m4/acl.m4
+++ b/m4/acl.m4
@@ -1,5 +1,5 @@
# acl.m4 - check for access control list (ACL) primitives
-# serial 26
+# serial 27
# Copyright (C) 2002, 2004-2023 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
@@ -17,7 +17,7 @@ AC_DEFUN([gl_FUNC_ACL_ARG],
])
-AC_DEFUN([gl_FUNC_ACL],
+AC_DEFUN_ONCE([gl_FUNC_ACL],
[
AC_REQUIRE([gl_FUNC_ACL_ARG])
AC_CHECK_FUNCS_ONCE([fchmod])
diff --git a/modules/qcopy-acl b/modules/qcopy-acl
index 8dd147927d..b89d8ecab6 100644
--- a/modules/qcopy-acl
+++ b/modules/qcopy-acl
@@ -10,6 +10,7 @@ acl-permissions [test "$use_xattr" != yes]
configure.ac:
gl_FUNC_XATTR
+AC_REQUIRE([gl_FUNC_ACL])
if test "$use_xattr" = yes; then
QCOPY_ACL_LIB="$LIB_XATTR"
else
