diff --git a/vlib/builtin/map.v b/vlib/builtin/map.v
index 2ea56e3eea..600ccaf1df 100644
--- a/vlib/builtin/map.v
+++ b/vlib/builtin/map.v
@@ -88,7 +88,7 @@ mut:
 	values      &u8 = unsafe { nil }
 }
 
-@[inline]
+@[inline; markused]
 fn new_dense_array(key_bytes int, value_bytes int) DenseArray {
 	cap := 8
 	return DenseArray{
@@ -103,18 +103,18 @@ fn new_dense_array(key_bytes int, value_bytes int) DenseArray {
 	}
 }
 
-@[inline]
+@[inline; markused]
 fn (d &DenseArray) key(i int) voidptr {
 	return unsafe { voidptr(d.keys + i * d.key_bytes) }
 }
 
 // for cgen
-@[inline]
+@[inline; markused]
 fn (d &DenseArray) value(i int) voidptr {
 	return unsafe { voidptr(d.values + i * d.value_bytes) }
 }
 
-@[inline]
+@[inline; markused]
 fn (d &DenseArray) has_index(i int) bool {
 	return d.deletes == 0 || unsafe { d.all_deleted[i] } == 0
 }
diff --git a/vlib/v/gen/c/fn.v b/vlib/v/gen/c/fn.v
index a70a3cfd13..0f7522ed13 100644
--- a/vlib/v/gen/c/fn.v
+++ b/vlib/v/gen/c/fn.v
@@ -15,6 +15,11 @@ fn (mut g Gen) is_used_by_main(node ast.FnDecl) bool {
 	}
 	mut is_used_by_main := true
 	if g.pref.skip_unused {
+		if node.is_markused {
+			// TODO for some reason markused walker doesn't set used_fns[key] true for
+			// [markused] fndecls
+			return true
+		}
 		fkey := node.fkey()
 		is_used_by_main = g.table.used_features.used_fns[fkey]
 		$if trace_skip_unused_fns ? {
diff --git a/vlib/v/markused/markused.v b/vlib/v/markused/markused.v
index 26e85f1153..b587c47557 100644
--- a/vlib/v/markused/markused.v
+++ b/vlib/v/markused/markused.v
@@ -357,7 +357,8 @@ pub fn mark_used(mut table ast.Table, mut pref_ pref.Preferences, ast_files []&a
 		pref:        pref_
 	)
 	// println( all_fns.keys() )
-	walker.mark_markused_fns() // tagged with `@[markused]`
+
+	walker.mark_markused_fn_decls() // tagged with `@[markused]`
 
 	walker.mark_markused_consts() // tagged with `@[markused]`
 	walker.mark_markused_globals() // tagged with `@[markused]`
diff --git a/vlib/v/markused/walker.v b/vlib/v/markused/walker.v
index 208b9d4440..56f855865e 100644
--- a/vlib/v/markused/walker.v
+++ b/vlib/v/markused/walker.v
@@ -117,7 +117,7 @@ pub fn (mut w Walker) mark_exported_fns() {
 	}
 }
 
-pub fn (mut w Walker) mark_markused_fns() {
+pub fn (mut w Walker) mark_markused_fn_decls() {
 	for _, mut func in w.all_fns {
 		if func.is_markused {
 			$if trace_skip_unused_markused_fns ? {