commit f520e28292d112ab1bd52d41567d89fb98cc5090
author Thomas Klausner <tk@giga.or.at> Mon Jul 13 11:20:57 2020
committer Thomas Klausner <tk@giga.or.at> Mon Jul 13 11:20:57 2020
tree f8152b23b97b2039902ec0592f253f7fd9d170fe
parent 4fdcd241a48387d1a3aecd04ca25a115a9a689f6

Replace include_guard.

For better backwards compat with cmake < 3.10.

cmake-compat/CheckLibraryExists.cmake

diff --git a/cmake-compat/CheckLibraryExists.cmake b/cmake-compat/CheckLibraryExists.cmake
index 6470dfd..76901ab 100644
--- a/cmake-compat/CheckLibraryExists.cmake
+++ b/cmake-compat/CheckLibraryExists.cmake
@@ -35,7 +35,10 @@
   CMAKE_REQUIRED_QUIET = execute quietly without messages
 #]=======================================================================]
 
-include_guard(GLOBAL)
+if(__CheckLibraryExists_cmake__)
+  return()
+endif()
+set(__CheckLibraryExists_cmake__ TRUE)
 
 macro(CHECK_LIBRARY_EXISTS LIBRARY FUNCTION LOCATION VARIABLE)
   if(NOT DEFINED "${VARIABLE}")

cmake-compat/CheckSymbolExists.cmake

diff --git a/cmake-compat/CheckSymbolExists.cmake b/cmake-compat/CheckSymbolExists.cmake
index 4f202c4..79d3d7d 100644
--- a/cmake-compat/CheckSymbolExists.cmake
+++ b/cmake-compat/CheckSymbolExists.cmake
@@ -58,7 +58,10 @@
   check_symbol_exists(fopen "stdio.h" HAVE_FOPEN)
 #]=======================================================================]
 
-include_guard(GLOBAL)
+if(__CheckSymbolExists_cmake__)
+  return()
+endif()
+set(__CheckSymbolExists_cmake__ TRUE)
 
 cmake_policy(PUSH)
 cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced