Fixed fontconfig cmake search and libclang isysroot issue on MacOS

CMakeLists.txt

@@ -59,7 +59,7 @@ if(APPLE)
 
   include_directories(/usr/local/opt/gettext/include)
   set(CMAKE_MACOSX_RPATH 1)
-  set(ENV{PKG_CONFIG_PATH} "$ENV{PKG_CONFIG_PATH}:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig:/usr/local/opt/libffi/lib/pkgconfig:/usr/local/opt/libsigc++@2/lib/pkgconfig:/usr/local/opt/zlib/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig")
+  set(ENV{PKG_CONFIG_PATH} "/opt/homebrew/opt/fontconfig/lib/pkgconfig:/usr/local/opt/fontconfig/lib/pkgconfig:$ENV{PKG_CONFIG_PATH}:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig:/usr/local/opt/libffi/lib/pkgconfig:/usr/local/opt/libsigc++@2/lib/pkgconfig:/usr/local/opt/zlib/lib/pkgconfig:/usr/local/opt/libxml2/lib/pkgconfig")
 endif()
 if(${CMAKE_SYSTEM_NAME} MATCHES FreeBSD)
   link_directories(/usr/local/lib)

src/compile_commands.cpp

@@ -123,6 +123,14 @@ std::vector<std::string> CompileCommands::get_arguments(const boost::filesystem:
     arguments.emplace_back(resource_path);
   }
 
+#ifdef __APPLE__
+  // Add -isysroot argument if it is missing on MacOS, which is needed by newer libclang
+  if(std::none_of(arguments.begin(), arguments.end(), [](const std::string &argument) { return argument == "-isysroot"; })) {
+    arguments.emplace_back("-isysroot");
+    arguments.emplace_back("/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk");
+  }
+#endif
+
   // Do not add -fretain-comments-from-system-headers if pch is used, since the pch was most likely made without this flag
   if(std::none_of(arguments.begin(), arguments.end(), [](const std::string &argument) { return argument == "-include-pch"; }))
     arguments.emplace_back("-fretain-comments-from-system-headers");