diff --git a/reference/opt/shaders-msl/frag/mrt-array.frag b/reference/opt/shaders-msl/frag/mrt-array.frag
new file mode 100644
index 00000000..1a84e620
--- /dev/null
+++ b/reference/opt/shaders-msl/frag/mrt-array.frag
@@ -0,0 +1,35 @@
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+struct main0_in
+{
+    float4 vB [[user(locn1)]];
+    float4 vA [[user(locn0)]];
+};
+
+struct main0_out
+{
+    float4 FragColor [[color(0)]][4];
+};
+
+// Implementation of the GLSL mod() function, which is slightly different than Metal fmod()
+template<typename Tx, typename Ty>
+Tx mod(Tx x, Ty y)
+{
+    return x - y * floor(x / y);
+}
+
+fragment main0_out main0(main0_in in [[stage_in]])
+{
+    main0_out out = {};
+    out.FragColor[0] = mod(in.vA, in.vB);
+    out.FragColor[1] = in.vA + in.vB;
+    out.FragColor[2] = in.vA - in.vB;
+    out.FragColor[3] = in.vA * in.vB;
+    return out;
+}
+
diff --git a/reference/shaders-msl/frag/mrt-array.frag b/reference/shaders-msl/frag/mrt-array.frag
new file mode 100644
index 00000000..1a84e620
--- /dev/null
+++ b/reference/shaders-msl/frag/mrt-array.frag
@@ -0,0 +1,35 @@
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+struct main0_in
+{
+    float4 vB [[user(locn1)]];
+    float4 vA [[user(locn0)]];
+};
+
+struct main0_out
+{
+    float4 FragColor [[color(0)]][4];
+};
+
+// Implementation of the GLSL mod() function, which is slightly different than Metal fmod()
+template<typename Tx, typename Ty>
+Tx mod(Tx x, Ty y)
+{
+    return x - y * floor(x / y);
+}
+
+fragment main0_out main0(main0_in in [[stage_in]])
+{
+    main0_out out = {};
+    out.FragColor[0] = mod(in.vA, in.vB);
+    out.FragColor[1] = in.vA + in.vB;
+    out.FragColor[2] = in.vA - in.vB;
+    out.FragColor[3] = in.vA * in.vB;
+    return out;
+}
+
diff --git a/shaders-msl/frag/mrt-array.frag b/shaders-msl/frag/mrt-array.frag
new file mode 100644
index 00000000..a8a8e492
--- /dev/null
+++ b/shaders-msl/frag/mrt-array.frag
@@ -0,0 +1,14 @@
+#version 310 es
+precision mediump float;
+
+layout(location = 0) out vec4 FragColor[4];
+layout(location = 0) in vec4 vA;
+layout(location = 1) in vec4 vB;
+
+void main()
+{
+	FragColor[0] = mod(vA, vB);
+	FragColor[1] = vA + vB;
+	FragColor[2] = vA - vB;
+	FragColor[3] = vA * vB;
+}
diff --git a/spirv_msl.cpp b/spirv_msl.cpp
index c210b541..50d56562 100644
--- a/spirv_msl.cpp
+++ b/spirv_msl.cpp
@@ -604,8 +604,9 @@ uint32_t CompilerMSL::add_interface_block(StorageClass storage)
 			BuiltIn builtin = BuiltIn(get_decoration(p_var->self, DecorationBuiltIn));
 
 			if (should_move_to_input_buffer(type_id, is_builtin, storage))
+			{
 				move_to_input_buffer(*p_var);
-
+			}
 			else if (!is_builtin || has_active_builtin(builtin, storage))
 			{
 				// Add a reference to the variable type to the interface struct.
@@ -679,8 +680,8 @@ bool CompilerMSL::should_move_to_input_buffer(uint32_t type_id, bool is_builtin,
 			if (storage == StorageClassInput)
 				SPIRV_CROSS_THROW("The fragment function stage_in structure may not include a matrix or array.");
 
-			if (storage == StorageClassOutput)
-				SPIRV_CROSS_THROW("The fragment function output structure may not include a matrix or array.");
+			//if (storage == StorageClassOutput)
+			//	SPIRV_CROSS_THROW("The fragment function output structure may not include a matrix or array.");
 		}
 	}