From 57fe147115ee718b4a019d17ecded5e3e5936ca0 Mon Sep 17 00:00:00 2001
From: Xu Zhen <xuzhen@users.noreply.github.com>
Date: Tue, 23 Jun 2020 12:23:41 +0800
Subject: [PATCH] Fixed CMake with MinGW 4.9

---
 CMakeLists.txt | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d426ffcf5..421e11377 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -106,6 +106,13 @@ else()  # minimum required standard
     set(CMAKE_CXX_STANDARD 11)
 endif()
 
+if ("${CMAKE_CXX17_STANDARD_COMPILE_OPTION}" STREQUAL "")
+    set(CMAKE_CXX_STANDARD 14)
+endif()
+if ("${CMAKE_CXX14_STANDARD_COMPILE_OPTION}" STREQUAL "")
+    set(CMAKE_CXX_STANDARD 11)
+endif()
+
 # Avoid using experimental c++1y (c++1z) standard even if the compiler announces cxx14 (cxx17)
 # in CMAKE_CXX_KNOWN_FEATURES and CMAKE_CXX_COMPILE_FEATURES
 # It is the case of clang 3.9, 4.0 (announces c++1z) and gcc 4.8 (announces c++1y)