From e8ec87abb504744c2cc5d39cb4ba0e48b4f7a1dc Mon Sep 17 00:00:00 2001
From: Marcin Zdun <mzdun@midnightbits.com>
Date: Tue, 15 Sep 2020 21:32:11 +0200
Subject: [PATCH] Compiler/library feature detection

---
 CMakeLists.txt | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index f9c6aef..ced9492 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -106,12 +106,26 @@ add_library(args STATIC
   "${CMAKE_CURRENT_BINARY_DIR}/include/args/version.hpp"
   )
 target_compile_options(args PRIVATE ${ADDITIONAL_WALL_FLAGS})
+target_compile_features(args PRIVATE cxx_std_17)
 target_include_directories(args
   PUBLIC
     ${CMAKE_CURRENT_SOURCE_DIR}/include
     ${CMAKE_CURRENT_BINARY_DIR}/include
   PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src)
 
+include(CheckCXXSourceCompiles)
+function(check_charconv)
+  check_cxx_source_compiles("#include <charconv>
+int main() {}" HAS_CHARCONV_)
+  set(HAS_CHARCONV ${HAS_CHARCONV_} PARENT)
+endfunction()
+check_cxx_source_compiles("#include <charconv>
+int main() {}" HAS_CHARCONV)
+
+if (NOT HAS_CHARCONV)
+  message(FATAL_ERROR "The compiler has no access to <charconv>")
+endif()
+
 ##################################################################
 ##  INSTALL
 ##################################################################