cgen: fix match option with case non option (fix #24047) (fix #24048) (#24051)

Author: felipensp

vlib/v/gen/c/cgen.v

@@ -2090,14 +2090,28 @@ fn (mut g Gen) stmts_with_tmp_var(stmts []ast.Stmt, tmp_var string) bool {
 							g.writeln(';')
 						} else {
 							// on assignment or struct field initialization
-							ret_typ := if g.inside_struct_init || g.inside_assign {
+							inside_assign_context := g.inside_struct_init
+								|| g.inside_assign
+								|| (!g.inside_return && g.inside_match_option)
+							ret_expr_typ := if inside_assign_context {
+								stmt.typ
+							} else {
+								g.fn_decl.return_type
+							}
+							ret_typ := if inside_assign_context {
 								stmt.typ
 							} else {
 								g.fn_decl.return_type.clear_flag(.option)
 							}
 							styp = g.base_type(ret_typ)
 							if stmt.expr is ast.CallExpr && stmt.expr.is_noreturn {
 								g.writeln(';')
+							} else if !ret_expr_typ.has_option_or_result()
+								&& !stmt.typ.has_option_or_result() && g.last_if_option_type != 0
+								&& !g.last_if_option_type.has_option_or_result() {
+								g.write('${tmp_var} = ')
+								g.expr_with_cast(stmt.expr, stmt.typ, ret_typ)
+								g.writeln(';')
 							} else {
 								g.write('_option_ok(&(${styp}[]) { ')
 								g.expr_with_cast(stmt.expr, stmt.typ, ret_typ)

vlib/v/gen/c/if.v

@@ -217,6 +217,11 @@ fn (mut g Gen) if_expr(node ast.IfExpr) {
 			}
 			g.inside_if_result = true
 			styp = styp.replace('*', '_ptr')
+		} else {
+			g.last_if_option_type = node.typ
+			defer {
+				g.last_if_option_type = tmp_if_option_type
+			}
 		}
 		cur_line = g.go_before_last_stmt()
 		g.empty_line = true

vlib/v/tests/options/option_match_case_test.v

@@ -0,0 +1,17 @@
+fn test_main() {
+	v := match 12 {
+		12 {
+			x := if true { 'b' } else { some_func()? }
+			assert x == 'b'
+			x
+		}
+		else {
+			none
+		}
+	}
+	assert v? == 'b'
+}
+
+fn some_func() ?string {
+	return 'a'
+}