Merge pull request #8 from andrey-starodubtsev/check_struct_has_member

`CheckStructHasMember` support

CMakeChecksCache/CheckStructHasMember.cmake

@@ -0,0 +1,34 @@
+# MIT License
+
+# Copyright (c) 2017-2018 Cristian Adam
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+include_guard(GLOBAL)
+
+cmake_minimum_required(VERSION 3.11)
+
+include(DumpCMakeVariables)
+include(${CMAKE_ROOT}/Modules/CheckStructHasMember.cmake)
+
+macro(check_struct_has_member struct member header variable)
+    _check_struct_has_member("${struct}" ${member} "${header}" ${variable} ${ARGN})
+    file(APPEND ${CMAKE_CHECKS_CACHE_FILE} "set(${variable} \"${${variable}}\" CACHE INTERNAL \"${struct} hash ${member} member\")\n")
+endmacro()
+