meson: Fix the check for --version-script support

At the time we do this check, version_script has not yet been generated,
so we have to use something else.

Signed-off-by: Simon McVittie <smcv@collabora.com>

dbus/Makefile.am

@@ -330,6 +330,7 @@ endif
 noinst_PROGRAMS =
 
 EXTRA_DIST += meson.build
+EXTRA_DIST += test-version-script
 
 # Add rules for code-coverage testing, as defined by AX_CODE_COVERAGE
 include $(top_srcdir)/aminclude_static.am

dbus/meson.build

@@ -172,9 +172,16 @@ version_script = configure_file(
     configuration: data_config,
 )
 
-version_flags = '-Wl,--version-script,@0@'.format(version_script)
-if not cc.has_link_argument(version_flags)
-  version_flags = []
+# We can't use version_script to check for support, because it hasn't been
+# generated yet, so use a static source file instead.
+if cc.has_link_argument(
+    '-Wl,--version-script,@0@'.format(
+        meson.current_source_dir() / 'test-version-script'
+    )
+)
+    version_flags = ['-Wl,--version-script,@0@'.format(version_script)]
+else
+    version_flags = []
 endif
 
 libdbus = library('dbus-1',

dbus/test-version-script

@@ -0,0 +1,10 @@
+NOT_REALLY_LIBDBUS_1_3 {
+  global:
+    dbus_*;
+  local:
+    *;
+};
+NOT_REALLY_LIBDBUS_PRIVATE_1.2.3 {
+  global:
+    _dbus_*;
+};