Index: CMakeLists.txt
--- CMakeLists.txt.orig
+++ CMakeLists.txt
@@ -63,10 +63,8 @@ else()
 
 	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${_FLAGS_COMMON} -fvisibility-inlines-hidden")
 	set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -O0 -g3")
-	set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3")
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${_FLAGS_COMMON}")
 	set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -O0 -g3")
-	set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -O3")
 
 	# Enable latest possible C standard
 	foreach(flag "-std=c2x" "-std=c11" "-std=c1x" "-std=c99")
@@ -117,7 +115,6 @@ if(WIN32)
 	add_definitions(-DUNICODE -D_UNICODE -D_SECURE_SCL=0 -D_ITERATOR_DEBUG_LEVEL=0 -D_CRT_SECURE_NO_DEPRECATE -DWIN32_LEAN_AND_MEAN -DVC_EXTRALEAN -DNOMINMAX)
 	include_directories("include/win32")
 else()
-	add_definitions(-D_POSIX_C_SOURCE=200112)
 	set(POPEN_PLUS_CPP "../include/posix/popen_plus.cpp" "../include/posix/popen_plus.hpp")
 	include_directories("include/posix")
 endif()