cgen: fix generic multiple indirections on print (fix #22793) (#25633)

Author: felipensp

vlib/v/gen/c/str.v

@@ -232,7 +232,7 @@ fn (mut g Gen) gen_expr_to_string(expr ast.Expr, etype ast.Type) {
 			if str_method_expects_ptr && !is_ptr && !typ.has_flag(.option) {
 				g.write('&')
 			} else if (!str_method_expects_ptr && is_ptr && !is_shared) || is_var_mut {
-				g.write('*')
+				g.write('*'.repeat(typ.nr_muls()))
 			} else {
 				if sym.is_c_struct() {
 					g.write(c_struct_ptr(sym, typ, str_method_expects_ptr))

vlib/v/tests/generics/generic_muls_test.v

@@ -0,0 +1,12 @@
+fn test_main() {
+	la := 'lalala'
+	la2 := &la
+	la3 := &la2
+	a(la3)
+}
+
+fn a[T](t &&T) {
+	println(t)
+	dump(t)
+	assert **t == 'lalala'
+}