I recently did a quick test of just-released PHP7 in my build and immediately noticed the following warnings: The issue occurs because PHP7 will deprecate PHP4 Style constructors. The Inspect library hasn't been maintained in about 6 years but it would be quite the chore to remove it from Hotaru core given it's used pretty much everywhere (and I'm not sure what a better library would be). @shibuya246, what do you think is the best way to approach this? Here are some ideas from WordPress. For those who are testing PHP7, please post any warnings or errors you see in this thread. Auditing the code is going to take some time and effort.