diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 945100a..6daad98 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -14,7 +14,6 @@ if (MSVC)
     set_source_files_properties(${src} PROPERTIES LANGUAGE CXX)
 endif()
 
-string(REPLACE "-O3" "-O2" CMAKE_C_FLAGS_RELEASE ${CMAKE_C_FLAGS_RELEASE})
 
 add_library                     (leptonica ${LIBRARY_TYPE} ${src} ${hdr})
 set_target_properties           (leptonica PROPERTIES VERSION   ${VERSION_PLAIN})