diff --git a/transformer_engine/common/CMakeLists.txt b/transformer_engine/common/CMakeLists.txt
index b9e2b907e0..645cdc34ba 100644
--- a/transformer_engine/common/CMakeLists.txt
+++ b/transformer_engine/common/CMakeLists.txt
@@ -79,6 +79,13 @@ if(NOT arch_120_index EQUAL -1)
   endif()
 endif()
 
+# If all architectures were moved to specific lists, set a placeholder
+# to avoid CMake's "CUDA_ARCHITECTURES is empty" error.
+# The actual arch flags are added per-source via COMPILE_OPTIONS.
+if(NOT CMAKE_CUDA_ARCHITECTURES)
+  set(CMAKE_CUDA_ARCHITECTURES OFF)
+endif()
+
 # cuDNN frontend API
 set(CUDNN_FRONTEND_INCLUDE_DIR
     "${CMAKE_CURRENT_SOURCE_DIR}/../../3rdparty/cudnn-frontend/include")