From 765ffa37eb058b5bef18b7ecc227145a5326668b Mon Sep 17 00:00:00 2001
From: Ruofan XU <47302112+SleepyRoy@users.noreply.github.com>
Date: Sat, 4 Jul 2020 17:36:33 +0800
Subject: [PATCH] cgen: fix == for mut arraay args (#5648)

---
 vlib/builtin/array_test.v | 21 +++++++++++++++++++++
 vlib/v/gen/cgen.v         |  8 +++++++-
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/vlib/builtin/array_test.v b/vlib/builtin/array_test.v
index ffde01cce7..d95b5ea964 100644
--- a/vlib/builtin/array_test.v
+++ b/vlib/builtin/array_test.v
@@ -877,3 +877,24 @@ fn test_plus_assign_string() {
 	a[0] += 'abc'
 	assert a == ['abc']
 }
+
+fn mut_arr_with_eq_in_fn(mut a []int) {
+	if a == [1,2,3,4] {
+		a[0] = 0
+	}
+	if [0,2,3,4] == a {
+		a[1] = 0	
+	}
+	if !(a != [0,0,3,4]) {
+		a[2] = 0	
+	}
+	if !([0,0,0,4] != a) {
+		a[3] = 0
+	}
+}
+
+fn test_mut_arr_with_eq_in_fn() {
+	mut a := [1,2,3,4]
+	mut_arr_with_eq_in_fn(mut a)
+	assert a == [0,0,0,0]
+}
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index c4e5be8b40..8b951a44d6 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -1879,8 +1879,14 @@ fn (mut g Gen) infix_expr(node ast.InfixExpr) {
 		} else if node.op == .ne {
 			g.write('!${ptr_typ}_arr_eq(')
 		}
+	    if node.left_type.is_ptr() {
+			g.write('*')
+		}
 		g.expr(node.left)
 		g.write(', ')
+		if node.right_type.is_ptr() {
+			g.write('*')
+		}
 		g.expr(node.right)
 		g.write(')')
 	} else if node.op in [.key_in, .not_in] {
@@ -2814,7 +2820,7 @@ fn (mut g Gen) assoc(node ast.Assoc) {
 fn (mut g Gen) gen_array_equality_fn(left table.Type) string {
 	left_sym := g.table.get_type_symbol(left)
 	typ_name := g.typ(left)
-	ptr_typ := typ_name[typ_name.index_after('_', 0) + 1..]
+	ptr_typ := typ_name[typ_name.index_after('_', 0) + 1..].trim('*')
 	elem_sym := g.table.get_type_symbol(left_sym.array_info().elem_type)
 	elem_typ := g.typ(left_sym.array_info().elem_type)
 	ptr_elem_typ := elem_typ[elem_typ.index_after('_', 0) + 1..]