From fe2da0a94f2d23387163081e1270f2954ef79a1d Mon Sep 17 00:00:00 2001
From: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat, 4 Jul 2020 21:13:28 -0500
Subject: [PATCH] Put -Wno-redundant-move behind a compiler check

This fixes a warning under Ubuntu 18.04's default gcc
(cc++ (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0)
---
 CMakeLists.txt              | 1 -
 cmake/ConfigureChecks.cmake | 7 ++++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1d0430429..3888cfce6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -50,7 +50,6 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra \
 -Wno-comment \
 -Wno-address \
 -Wno-strict-aliasing \
--Wno-redundant-move \
 ")
 
 # Disable exception handling.
diff --git a/cmake/ConfigureChecks.cmake b/cmake/ConfigureChecks.cmake
index 1b003add6..02943124c 100644
--- a/cmake/ConfigureChecks.cmake
+++ b/cmake/ConfigureChecks.cmake
@@ -4,15 +4,20 @@
 # `wcstod_l` is a GNU-extension, sometimes hidden behind GNU-related defines.
 # This is the case for at least Cygwin and Newlib.
 list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_GNU_SOURCE=1)
+include(CheckCXXCompilerFlag)
 
 if(APPLE)
-    include(CheckCXXCompilerFlag)
     check_cxx_compiler_flag("-Werror=unguarded-availability" REQUIRES_UNGUARDED_AVAILABILITY)
     if(REQUIRES_UNGUARDED_AVAILABILITY)
         list(APPEND CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} "-Werror=unguarded-availability")
     endif()
 endif()
 
+check_cxx_compiler_flag("-Wno-redundant-move" HAS_NO_REDUNDANT_MOVE)
+if (HAS_NO_REDUNDANT_MOVE)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-redundant-move")
+endif()
+
 # Try using CMake's own logic to locate curses/ncurses
 find_package(Curses)
 if(NOT ${CURSES_FOUND})