nss: Fix tst-nss-files-alias-truncated for default --as-needed linking

Linking to the NSS module directly does not work if the linker defaults
to --as-needed because it will remove the apparently unused DSO
reference and not generate a DT_NEEDED entry.  Use an explicit dlopen
call, like in the other chroot tests involving NSS modules.

1 files changed, 5 insertions, 2 deletions

diff --git a/nss/tst-nss-files-alias-truncated.c b/nss/tst-nss-files-alias-truncated.c
index 2d6aba3c0e..029ae6a2a7 100644
--- a/nss/tst-nss-files-alias-truncated.c
+++ b/nss/tst-nss-files-alias-truncated.c
@@ -17,11 +17,13 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <aliases.h>
+#include <gnu/lib-names.h>
 #include <nss.h>
 #include <stddef.h>
 #include <support/check.h>
 #include <support/namespace.h>
 #include <support/test-driver.h>
+#include <support/xdlfcn.h>
 #include <support/xunistd.h>
 
 static void
@@ -42,8 +44,9 @@ in_chroot (void *closure)
 static int
 do_test (void)
 {
-  /* nss_files has already been loaded via DT_NEEDED, outside the
-     chroot.  */
+  /* Make sure we don't try to load the module in the chroot.  */
+  xdlopen (LIBNSS_FILES_SO, RTLD_NOW);
+
   __nss_configure_lookup ("aliases", "files");
 
   support_become_root ();