Comment 5 for bug 1821752

Looking more at the code the new behaviour is actually wanted. Statically linked binaries do not lookup in the default lib search patch by default (DF_1_NODEFLIB is defined as "Ignore default lib search path."):

--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -91,6 +91,7 @@ static struct link_map _dl_main_map =
     .l_scope = _dl_main_map.l_scope_mem,
     .l_local_scope = { &_dl_main_map.l_searchlist },
     .l_used = 1,
+ .l_flags_1 = DF_1_NODEFLIB,
     .l_tls_offset = NO_TLS_OFFSET,
     .l_serial = 1,
   };

This means that the dlopen calls from nss/nsswitch.c do not look for the default search path. In addition to that it means that the dlopen behavior for static binaries also has changed and doesn't support loading objects without an absolute path. This is conform to the POSIX specification ("Otherwise, file is used in an implementation-defined manner to yield a pathname."), but do we really want such a behavior change?

Concerning the NSS support we should probably switch it to an absolute path. In the meantime this can be workarounded by using LD_LIBRARY_PATH