From e1a37d0430d64654b816a64e27df19146211b2f1 Mon Sep 17 00:00:00 2001
From: Roelf-Jilling <r-j.wolthuis@live.com>
Date: Mon, 13 Jan 2020 20:17:24 +0100
Subject: [PATCH] Suppress -Wundefined-func-template for C++17 Clang v5.0.x and
 AppleClang 9.1

Warning appears on v5.0.2 from apt.llvm.org and Ubuntu provided v5.0.1
---
 tests/CMakeLists.txt | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 5c93a9a..680bd5e 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -79,7 +79,14 @@ else()
           -Wno-weak-vtables
         >
         $<$<CXX_COMPILER_ID:Clang>:
-          $<$<CXX_COMPILER_VERSION:5.0.2>:-Wno-undefined-func-template>
+          $<$<AND:$<VERSION_GREATER:$<CXX_COMPILER_VERSION>,4.99>,$<VERSION_LESS:$<CXX_COMPILER_VERSION>,6>>:
+            $<$<EQUAL:${GSL_CXX_STANDARD},17>:-Wno-undefined-func-template>
+          >
+        >
+        $<$<CXX_COMPILER_ID:AppleClang>:
+          $<$<AND:$<VERSION_GREATER:$<CXX_COMPILER_VERSION>,9.1>,$<VERSION_LESS:$<CXX_COMPILER_VERSION>,10>>:
+            $<$<EQUAL:${GSL_CXX_STANDARD},17>:-Wno-undefined-func-template>
+          >
         >
     )
 endif(MSVC)