diff --git a/.editorconfig b/.editorconfig
index b4b89fc..37342ee 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -9,8 +9,9 @@ insert_final_newline = true
 trim_trailing_whitespace = true
 indent_style = space
 indent_size = 4
+tab_width = 8
 
-[Makefile,Makefile.*,rules]
+[{Makefile,Makefile.*,rules,*.m4}]
 indent_style = tab
 indent_size = 8