diff --git a/CMakeLists.txt b/CMakeLists.txt
index 41f9489d..f432f851 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -39,8 +39,8 @@ set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_C_STANDARD 11)
 include(Coverage)
 include(GenerateExportHeader)
-set(CMAKE_CXX_FLAGS "-Wall -pedantic -Werror ${CMAKE_CXX_FLAGS}")
-set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -Wall -pedantic -Werror -Werror=return-type")
+set(CMAKE_CXX_FLAGS " -Wall ${CMAKE_CXX_FLAGS}")
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -Werror=return-type")
 
 # cmake code needed for the coverity scan upload
 include(Coverity)
@@ -74,12 +74,11 @@ set(QUAZIP_VERSION "0.7.1")
 if(NOT EXISTS ${CMAKE_BINARY_DIR}/quazip-${QUAZIP_VERSION}.tar.gz)
 	file(DOWNLOAD http://downloads.sourceforge.net/project/quazip/quazip/${QUAZIP_VERSION}/quazip-${QUAZIP_VERSION}.tar.gz ${CMAKE_BINARY_DIR}/quazip-${QUAZIP_VERSION}.tar.gz)
 endif()
-set(QUAZIP_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-c++11-long-long")
 ExternalProject_Add(QuaZIP
 	SOURCE_DIR <BINARY_DIR>/../Source/quazip-${QUAZIP_VERSION}
 	DOWNLOAD_COMMAND ${CMAKE_COMMAND} -E chdir <SOURCE_DIR>/.. ${CMAKE_COMMAND} -E tar xzf ${CMAKE_BINARY_DIR}/quazip-${QUAZIP_VERSION}.tar.gz
 	PATCH_COMMAND patch -p0 -i ${CMAKE_SOURCE_DIR}/quazip.patch
-	CMAKE_ARGS -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER} -DCMAKE_CXX_FLAGS=${QUAZIP_CXX_FLAGS} -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG} -DCMAKE_PREFIX_PATH=${CMAKE_PREFIX_PATH} -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
+	CMAKE_ARGS -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER} -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS} -DCMAKE_CXX_FLAGS_DEBUG=${CMAKE_CXX_FLAGS_DEBUG} -DCMAKE_PREFIX_PATH=${CMAKE_PREFIX_PATH} -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
 )
 include_directories("${CMAKE_BINARY_DIR}/External/Install/QuaZIP/include/quazip")
 if(UNIX)