diff --git a/external/vulkancts/modules/vulkan/binding_model/vktBindingDescriptorSetRandomTests.cpp b/external/vulkancts/modules/vulkan/binding_model/vktBindingDescriptorSetRandomTests.cpp
index 15e93db..0689313 100644
--- a/external/vulkancts/modules/vulkan/binding_model/vktBindingDescriptorSetRandomTests.cpp
+++ b/external/vulkancts/modules/vulkan/binding_model/vktBindingDescriptorSetRandomTests.cpp
@@ -700,6 +700,7 @@
 				"  uvec4 color = (accum != 0) ? uvec4(0,0,0,0) : uvec4(1,0,0,1);\n"
 				"  imageStore(image0_0, ivec2(gl_VertexIndex % " << DIM << ", gl_VertexIndex / " << DIM << "), color);\n"
 				"  gl_PointSize = 1.0f;\n"
+				"  gl_Position = vec4(0.0f, 0.0f, 0.0f, 1.0f);\n"
 				"}\n";
 
 			programCollection.glslSources.add("test") << glu::VertexSource(vss.str());
diff --git a/external/vulkancts/modules/vulkan/memory_model/vktMemoryModelMessagePassing.cpp b/external/vulkancts/modules/vulkan/memory_model/vktMemoryModelMessagePassing.cpp
index c48728b..6208947 100644
--- a/external/vulkancts/modules/vulkan/memory_model/vktMemoryModelMessagePassing.cpp
+++ b/external/vulkancts/modules/vulkan/memory_model/vktMemoryModelMessagePassing.cpp
@@ -406,8 +406,9 @@
 			"   uint bufferCoord        = gl_VertexIndex;\n"
 			"   uint partnerBufferCoord = subgroupShuffleXor(gl_VertexIndex, gl_SubgroupSize-1);\n"
 			"   ivec2 imageCoord        = ivec2(gl_VertexIndex % (DIM*NUM_WORKGROUP_EACH_DIM), gl_VertexIndex / (DIM*NUM_WORKGROUP_EACH_DIM));\n"
-			"   ivec2 partnerImageCoord = subgroupShuffleXor(imageCoord, gl_SubgroupSize-1);\n\n"
-			"   gl_PointSize			= 1.0f;\n\n";
+			"   ivec2 partnerImageCoord = subgroupShuffleXor(imageCoord, gl_SubgroupSize-1);\n"
+			"   gl_PointSize            = 1.0f;\n"
+			"   gl_Position             = vec4(0.0f, 0.0f, 0.0f, 1.0f);\n\n";
 			break;
 		case STAGE_FRAGMENT:
 			css <<
@@ -456,8 +457,9 @@
 			"   uint bufferCoord        = globalId.y * DIM*NUM_WORKGROUP_EACH_DIM + globalId.x;\n"
 			"   uint partnerBufferCoord = partnerGlobalId.y * DIM*NUM_WORKGROUP_EACH_DIM + partnerGlobalId.x;\n"
 			"   ivec2 imageCoord        = globalId;\n"
-			"   ivec2 partnerImageCoord = partnerGlobalId;\n\n"
-			"   gl_PointSize			= 1.0f;\n\n";
+			"   ivec2 partnerImageCoord = partnerGlobalId;\n"
+			"   gl_PointSize            = 1.0f;\n"
+			"   gl_Position             = vec4(0.0f, 0.0f, 0.0f, 1.0f);\n\n";
 			break;
 		case STAGE_FRAGMENT:
 			css <<