diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9c299df2d78c1bef07c8358f12c125a8fcebaef6..dca7dcc5cc0fa5ca60d8f4ef8c2eeba767065e93 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -531,7 +531,7 @@ endif()
 
 set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${MARCH}")
 
-set(MGB_ENABLE_IMPERATIVE, ${MGE_BUILD_XXX})
+set(MGB_ENABLE_IMPERATIVE ${MGE_BUILD_XXX})
 # Write out megbrain_build_config.h
 # It defines macros needed by both megbrain and dnn
 configure_file(src/megbrain_build_config.h.in ${CMAKE_CURRENT_BINARY_DIR}/genfiles/megbrain_build_config.h)