diff --git a/cmake/TaichiCore.cmake b/cmake/TaichiCore.cmake
index 3096832be40c7..1a41bc2020552 100644
--- a/cmake/TaichiCore.cmake
+++ b/cmake/TaichiCore.cmake
@@ -379,7 +379,9 @@ if (TI_WITH_VULKAN)
 
     target_include_directories(${CORE_LIBRARY_NAME} PRIVATE external/SPIRV-Headers/include)
     target_include_directories(${CORE_LIBRARY_NAME} PRIVATE external/SPIRV-Reflect)
-    target_include_directories(${CORE_LIBRARY_NAME} PRIVATE external/VulkanMemoryAllocator/include)
+
+    # By specifying SYSTEM, we suppressed the warnings from third-party headers.
+    target_include_directories(${CORE_LIBRARY_NAME} SYSTEM PRIVATE external/VulkanMemoryAllocator/include)
 
     if (LINUX)
         # shaderc requires pthread
diff --git a/taichi/backends/vulkan/vulkan_device.cpp b/taichi/backends/vulkan/vulkan_device.cpp
index 62b1b4fe6b865..a739758e69f88 100644
--- a/taichi/backends/vulkan/vulkan_device.cpp
+++ b/taichi/backends/vulkan/vulkan_device.cpp
@@ -278,7 +278,7 @@ void VulkanPipeline::create_descriptor_set_layout(const Params &params) {
 
       for (auto var : variables) {
         // We want to remove auxiliary outputs such as frag depth
-        if (var->built_in == -1) {
+        if (static_cast<int>(var->built_in) == -1) {
           render_target_count++;
         }
       }