diff --git a/meson.build b/meson.build
index 36314f7157..d719160a1f 100644
--- a/meson.build
+++ b/meson.build
@@ -884,8 +884,9 @@ libcrypt = cc.find_library('crypt')
 
 crypt_header = conf.get('HAVE_CRYPT_H') == 1 ? '''#include <crypt.h>''' : '''#include <unistd.h>'''
 foreach ident : [
-        ['crypt_ra',          crypt_header],
-        ['crypt_gensalt_ra',  crypt_header]]
+        ['crypt_ra',               crypt_header],
+        ['crypt_preferred_method', crypt_header],
+        ['crypt_gensalt_ra',       crypt_header]]
 
         have = cc.has_function(ident[0], prefix : ident[1], args : '-D_GNU_SOURCE',
                                dependencies : libcrypt)
diff --git a/src/shared/libcrypt-util.c b/src/shared/libcrypt-util.c
index c5d98671bd..8a46ace205 100644
--- a/src/shared/libcrypt-util.c
+++ b/src/shared/libcrypt-util.c
@@ -40,7 +40,11 @@ int make_salt(char **ret) {
 
         e = secure_getenv("SYSTEMD_CRYPT_PREFIX");
         if (!e)
+#if HAVE_CRYPT_PREFERRED_METHOD
                 e = crypt_preferred_method();
+#else
+                e = "$6$";
+#endif
 
         log_debug("Generating salt for hash prefix: %s", e);