parser: store FnDecl body position and use for scope

vlib/v/ast/ast.v

@@ -213,6 +213,7 @@ pub:
 	is_builtin    bool // this function is defined in builtin/strconv
 	ctdefine      string // has [if myflag] tag
 	pos           token.Position
+	body_pos      token.Position
 	file          string
 pub mut:
 	return_type   table.Type

vlib/v/gen/fn.v

@@ -161,7 +161,7 @@ fn (mut g Gen) gen_fn_decl(it ast.FnDecl) {
 	// ////////////
 	if g.autofree {
 		// println('\n\ncalling free for fn $it.name')
-		g.free_scope_vars(it.pos.pos + it.pos.len/2)
+		g.free_scope_vars(it.body_pos.pos)
 	}
 	// /////////
 	if is_main {

vlib/v/parser/fn.v

@@ -231,6 +231,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 	// Body
 	mut stmts := []ast.Stmt{}
 	no_body := p.tok.kind != .lcbr
+	body_start_pos := p.peek_tok.position()
 	if p.tok.kind == .lcbr {
 		stmts = p.parse_block_no_scope()
 	}
@@ -255,7 +256,7 @@ fn (mut p Parser) fn_decl() ast.FnDecl {
 		is_js: is_js
 		no_body: no_body
 		pos: start_pos.extend(end_pos)
-		file: p.file_name
+		body_pos: body_start_pos
 		is_builtin: p.builtin_mod || p.mod in util.builtin_module_parts
 		ctdefine: ctdefine
 	}
@@ -306,7 +307,6 @@ fn (mut p Parser) anon_fn() ast.AnonFn {
 			is_anon: true
 			no_body: no_body
 			pos: pos
-			file: p.file_name
 		}
 		typ: typ
 	}