+# hack for objc4/runtime/objc-internal.h
+AS_IF([test -n "$apple_objc4_source_runtime_path"], [
+ saveCPPFLAGS="$CPPFLAGS"
+ CPPFLAGS="$CPPFLAGS -I."
+ ln -fsh "$apple_objc4_source_runtime_path" objc
+])
+AC_CHECK_HEADER([objc/objc-internal.h], [
+ AC_DEFINE(USE_OBJC, 1, [Define to use Objective-C runtime])
+ have_objc=true], [have_objc=false],
+ [#include <objc/runtime.h>]
+)
+AS_IF([test -n "$apple_objc4_source_runtime_path"], [
+ rm -f objc
+ CPPFLAGS="$saveCPPFLAGS"
+ AC_CONFIG_COMMANDS([src/objc],
+ [ln -fsh "$apple_objc4_source_runtime_path" src/objc],
+ [apple_objc4_source_runtime_path="$apple_objc4_source_runtime_path"])
+])
+AM_CONDITIONAL(USE_OBJC, $have_objc)