diff --git a/gtsam/CMakeLists.txt b/gtsam/CMakeLists.txt
index 2ca83e093..c4ad0a755 100644
--- a/gtsam/CMakeLists.txt
+++ b/gtsam/CMakeLists.txt
@@ -106,7 +106,7 @@ add_library(gtsam ${gtsam_srcs})
 target_link_libraries(gtsam PUBLIC ${GTSAM_BOOST_LIBRARIES})
 target_link_libraries(gtsam PUBLIC ${GTSAM_ADDITIONAL_LIBRARIES})
 
-if(${CMAKE_BUILD_TYPE} STREQUAL "Release")
+if("${CMAKE_BUILD_TYPE}" STREQUAL "Release")
   # Suppress warnings if Release build
   target_compile_options(gtsam PRIVATE -w)
 endif()