From b89bf34fa1e6185239be4cceea4c1a4bc1983e42 Mon Sep 17 00:00:00 2001
From: davidf <dforsten@gmail.com>
Date: Sun, 26 Apr 2020 19:59:39 +0200
Subject: [PATCH] Fix for cmake-conan issue #225 - Compile error on
 configuration on MacOS The sysroot option is not set when using
 `/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/c++`,
 needs to be added explicitly.

---
 conan.cmake | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/conan.cmake b/conan.cmake
index 6425a9fd..4abecf88 100644
--- a/conan.cmake
+++ b/conan.cmake
@@ -264,9 +264,13 @@ function(conan_cmake_detect_unix_libcxx result)
         endif()
     endforeach()
 
+    if(APPLE)
+        set(xcode_sysroot_option "--sysroot=${CMAKE_OSX_SYSROOT}")
+    endif()
+
     execute_process(
         COMMAND ${CMAKE_COMMAND} -E echo "#include <string>"
-        COMMAND ${CMAKE_CXX_COMPILER} -x c++ ${compile_options} -E -dM -
+        COMMAND ${CMAKE_CXX_COMPILER} -x c++ ${xcode_sysroot_option} ${compile_options} -E -dM -
         OUTPUT_VARIABLE string_defines
     )