From 507d724ee6440648ede729633f8031c86486f620 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Mon, 9 Nov 2020 11:54:41 +0100
Subject: [PATCH] autofree: free before return tests

---
 vlib/os/os_nix.c.v                           |  3 +++
 vlib/v/gen/cgen.v                            | 11 ++++++-----
 vlib/v/gen/fn.v                              |  3 ++-
 vlib/v/tests/valgrind/1.strings_and_arrays.v | 18 ++++++++++++++++++
 4 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/vlib/os/os_nix.c.v b/vlib/os/os_nix.c.v
index 7c44662ea6..1b247ca813 100644
--- a/vlib/os/os_nix.c.v
+++ b/vlib/os/os_nix.c.v
@@ -110,6 +110,9 @@ pub fn mkdir(path string) ?bool {
 	}
 	*/
 	apath := real_path(path)
+	defer {
+		apath.free()
+	}
 	/*
 	$if linux {
 		$if !android {
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index ab797017b0..817d99f5d9 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -1003,11 +1003,12 @@ fn (mut g Gen) stmt(node ast.Stmt) {
 			af := g.pref.autofree && node.exprs.len > 0 && node.exprs[0] is ast.CallExpr && !g.is_builtin_mod
 			if g.pref.autofree {
 				g.writeln('// ast.Return free')
-				// if af {
-				// g.autofree_call_pregen(node.exprs[0] as ast.CallExpr)
-				// }
-				// g.autofree_scope_vars(node.pos.pos)
-				g.write_autofree_stmts_when_needed(node)
+				if af {
+					g.writeln('//af tmp')
+					// g.autofree_call_pregen(node.exprs[0] as ast.CallExpr)
+				}
+				// g.autofree_scope_vars(node.pos.pos - 1)
+				// g.write_autofree_stmts_when_needed(node)
 			}
 			g.return_statement(node, af)
 		}
diff --git a/vlib/v/gen/fn.v b/vlib/v/gen/fn.v
index 2f773835b4..eebfdff8c3 100644
--- a/vlib/v/gen/fn.v
+++ b/vlib/v/gen/fn.v
@@ -186,6 +186,7 @@ fn (mut g Gen) gen_fn_decl(it ast.FnDecl, skip bool) {
 	}
 }
 
+/*
 fn (mut g Gen) write_autofree_stmts_when_needed(r ast.Return) {
 	// TODO: write_autofree_stmts_when_needed should account for the current local scope vars.
 	// TODO: write_autofree_stmts_when_needed should not free the returned variables.
@@ -195,7 +196,7 @@ fn (mut g Gen) write_autofree_stmts_when_needed(r ast.Return) {
 	// g.writeln(g.autofree_scope_vars(g.fn_decl.body_pos.pos))
 	// g.writeln('//--------------------------------------------------- ') // //g.write( g.autofree_scope_vars(r.pos.pos) )
 }
-
+*/
 fn (mut g Gen) write_defer_stmts_when_needed() {
 	if g.defer_stmts.len > 0 {
 		g.write_defer_stmts()
diff --git a/vlib/v/tests/valgrind/1.strings_and_arrays.v b/vlib/v/tests/valgrind/1.strings_and_arrays.v
index 884aa3e51f..238966ca66 100644
--- a/vlib/v/tests/valgrind/1.strings_and_arrays.v
+++ b/vlib/v/tests/valgrind/1.strings_and_arrays.v
@@ -1,3 +1,5 @@
+import os
+
 // This program is built and run via Valgrind to ensure there are no leaks with -autofree
 fn simple() {
 	nums := [1, 2, 3] // local array must be freed
@@ -218,6 +220,20 @@ fn free_inside_opt_block() {
 	}
 }
 
+fn free_before_return() {
+	s := 'a' + 'b'
+	println(s)
+	if true {
+		return
+	}
+}
+
+fn free_before_return_bool() bool {
+	s := 'a' + 'b'
+	println(s)
+	return true
+}
+
 fn main() {
 	println('start')
 	simple()
@@ -236,6 +252,8 @@ fn main() {
 	q := if_expr()
 	s := return_if_expr()
 	free_inside_opt_block()
+	// free_before_return()
+	// free_before_return_bool()
 	// free_map()
 	// loop_map()
 	println('end')