--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -59,7 +59,7 @@ ELSE (WIN32)
       "${CMAKE_C_FLAGS} -std=c99 -pedantic -Wpointer-arith -Wno-format-y2k -Wstrict-prototypes -Wmissing-declarations -Wnested-externs -Wextra	-Wundef -Wwrite-strings -Wold-style-definition -Wredundant-decls -Wno-unused-parameter -Wno-sign-compare -Wmissing-prototypes")
 
   SET(CMAKE_C_FLAGS_DEBUG "-DDEBUG -g")
-  SET(CMAKE_C_FLAGS_RELEASE "-DNDEBUG -O2 -Wuninitialized")
+  SET(CMAKE_C_FLAGS_RELEASE "$ENV{OPTFLAGS} -Wuninitialized")
 ENDIF (WIN32)