diff --git a/libs/vkd3d-shader/dxil.c b/libs/vkd3d-shader/dxil.c
index c66b0593..5db9d6da 100644
--- a/libs/vkd3d-shader/dxil.c
+++ b/libs/vkd3d-shader/dxil.c
@@ -10315,6 +10315,21 @@ static enum vkd3d_result sm6_parser_init(struct sm6_parser *sm6, struct vsir_pro
     sm6->ptr = &sm6->start[1];
     sm6->bitpos = 2;
 
+    switch (program->shader_version.type)
+    {
+        case VKD3D_SHADER_TYPE_HULL:
+        case VKD3D_SHADER_TYPE_DOMAIN:
+            break;
+
+        default:
+            if (program->patch_constant_signature.element_count != 0)
+            {
+                WARN("The patch constant signature only makes sense for Hull and Domain Shaders, ignoring it.\n");
+                shader_signature_cleanup(&program->patch_constant_signature);
+            }
+            break;
+    }
+
     input_signature = &program->input_signature;
     output_signature = &program->output_signature;
     patch_constant_signature = &program->patch_constant_signature;
diff --git a/libs/vkd3d-shader/tpf.c b/libs/vkd3d-shader/tpf.c
index 89b3f56d..b097aa7f 100644
--- a/libs/vkd3d-shader/tpf.c
+++ b/libs/vkd3d-shader/tpf.c
@@ -2914,6 +2914,21 @@ int tpf_parse(const struct vkd3d_shader_compile_info *compile_info, uint64_t con
     if (program->shader_version.type == VKD3D_SHADER_TYPE_HULL)
         uninvert_used_masks(&program->patch_constant_signature);
 
+    switch (program->shader_version.type)
+    {
+        case VKD3D_SHADER_TYPE_HULL:
+        case VKD3D_SHADER_TYPE_DOMAIN:
+            break;
+
+        default:
+            if (program->patch_constant_signature.element_count != 0)
+            {
+                WARN("The patch constant signature only makes sense for Hull and Domain Shaders, ignoring it.\n");
+                shader_signature_cleanup(&program->patch_constant_signature);
+            }
+            break;
+    }
+
     if (!shader_sm4_parser_validate_signature(&sm4, &program->input_signature,
             sm4.input_register_masks, "Input")
             || !shader_sm4_parser_validate_signature(&sm4, &program->output_signature,
diff --git a/libs/vkd3d-shader/vkd3d_shader_main.c b/libs/vkd3d-shader/vkd3d_shader_main.c
index de483203..a996aaa1 100644
--- a/libs/vkd3d-shader/vkd3d_shader_main.c
+++ b/libs/vkd3d-shader/vkd3d_shader_main.c
@@ -1846,6 +1846,8 @@ void shader_signature_cleanup(struct shader_signature *signature)
     }
     vkd3d_free(signature->elements);
     signature->elements = NULL;
+    signature->elements_capacity = 0;
+    signature->element_count = 0;
 }
 
 int vkd3d_shader_parse_input_signature(const struct vkd3d_shader_code *dxbc,