doctor: check for DYLD_FALLBACK_LIBRARY_PATH

Library/Homebrew/cmd/doctor.rb

@@ -573,7 +573,7 @@ def check_for_config_scripts
   end
 end
 
-def check_for_dyld_vars
+def check_for_DYLD_LIBRARY_PATH
   if ENV['DYLD_LIBRARY_PATH']
     <<-EOS.undent
       Setting DYLD_LIBRARY_PATH can break dynamic linking.
@@ -582,6 +582,15 @@ def check_for_dyld_vars
   end
 end
 
+def check_for_DYLD_FALLBACK_LIBRARY_PATH
+  if ENV['DYLD_FALLBACK_LIBRARY_PATH']
+    <<-EOS.undent
+      Setting DYLD_FALLBACK_LIBRARY_PATH can break dynamic linking.
+      You should probably unset it.
+    EOS
+  end
+end
+
 def check_for_DYLD_INSERT_LIBRARIES
   if ENV['DYLD_INSERT_LIBRARIES']
     <<-EOS.undent