diff --git a/meson.build b/meson.build
index 1e37a5a..3907058 100644
--- a/meson.build
+++ b/meson.build
@@ -29,7 +29,7 @@ accountsserviceinterfacesdir = join_paths(datadir, 'accountsservice', 'interface
 # FIXME: pam.pc doesn’t exist
 pamlibdir = get_option('pamlibdir')
 if pamlibdir == ''
-  pamlibdir = join_paths(prefix, libdir.split('/')[-1], 'security')
+  pamlibdir = join_paths(libdir, 'security')
 endif
 
 dbus = dependency('dbus-1')