diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index d724257b53..765ac9d34a 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -2168,8 +2168,9 @@ pub fn (mut c Checker) expr(node_ ast.Expr) ast.Type {
 				return ast.void_type
 			}
 
-			tsym := c.table.sym(node.expr_type)
-			c.table.dumps[int(node.expr_type)] = tsym.cname
+			unwrapped_expr_type := c.unwrap_generic(node.expr_type)
+			tsym := c.table.sym(unwrapped_expr_type)
+			c.table.dumps[int(unwrapped_expr_type)] = tsym.cname
 			node.cname = tsym.cname
 			return node.expr_type
 		}
diff --git a/vlib/v/tests/inout/dump_generic_fn_mut_arg.out b/vlib/v/tests/inout/dump_generic_fn_mut_arg.out
new file mode 100644
index 0000000000..e8e6b5b7e7
--- /dev/null
+++ b/vlib/v/tests/inout/dump_generic_fn_mut_arg.out
@@ -0,0 +1 @@
+[vlib/v/tests/inout/dump_generic_fn_mut_arg.vv:11] t: &Reptile{}
diff --git a/vlib/v/tests/inout/dump_generic_fn_mut_arg.vv b/vlib/v/tests/inout/dump_generic_fn_mut_arg.vv
new file mode 100644
index 0000000000..35478ff40d
--- /dev/null
+++ b/vlib/v/tests/inout/dump_generic_fn_mut_arg.vv
@@ -0,0 +1,12 @@
+module main
+
+pub struct Reptile {}
+
+fn main() {
+	mut r := Reptile{}
+	do(mut r)
+}
+
+pub fn do<T>(mut t T) {
+	dump(t)
+}