diff --git a/CMakeLists.txt b/CMakeLists.txt
index 521ef93..a637866 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -114,12 +114,6 @@ set(NVIM_API_LEVEL 11)         # Bump this after any API change.
 set(NVIM_API_LEVEL_COMPAT 0)  # Adjust this after a _breaking_ API change.
 set(NVIM_API_PRERELEASE false)
 
-# Default to -O2 on release builds.
-if(CMAKE_C_FLAGS_RELEASE MATCHES "-O3")
-  message(STATUS "Replacing -O3 in CMAKE_C_FLAGS_RELEASE with -O2")
-  string(REPLACE "-O3" "-O2" CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE}")
-endif()
-
 # Build-type: RelWithDebInfo
 
 # /Og means something different in MSVC
