diff --git a/os/meson.build b/os/meson.build
index ab28fc4ed89fb549612e999bae6cc4e4ee507864..85b445f20fb3aa7377e67f2cfa5b91d36d492929 100644
--- a/os/meson.build
+++ b/os/meson.build
@@ -58,7 +58,7 @@ rpc_dep = []
 if get_option('secure-rpc')
     # prefer libtirpc (if available), otherwise ensure RPC functions are
     # provided by libc.
-    rpc_dep = dependency('libtirpc', required: false)
+    rpc_dep = dependency('libtirpc', required: false, include_type: 'system')
     if not (rpc_dep.found() or cc.has_header('rpc/rpc.h'))
         error('secure-rpc requested, but neither libtirpc or libc RPC support were found')
     endif