diff --git a/src/add-ons/kernel/file_systems/bfs/Jamfile b/src/add-ons/kernel/file_systems/bfs/Jamfile
index 3d244bcef5..d0d34a81f1 100644
--- a/src/add-ons/kernel/file_systems/bfs/Jamfile
+++ b/src/add-ons/kernel/file_systems/bfs/Jamfile
@@ -18,8 +18,8 @@ SubDir OBOS_TOP src add-ons kernel file_systems bfs ;
 	}
 
 	defines = [ FDefines $(defines) ] ;
-	SubDirCcFlags $(defines) ;
-	SubDirC++Flags $(defines) ;
+	SubDirCcFlags $(defines) -Wall -Wno-multichar ;
+	SubDirC++Flags $(defines) -Wall -Wno-multichar ;
 }
 
 R5KernelAddon obfs : [ FDirName kernel file_systems bfs ] :