HPE_INVALID_HEADER_TOKEN on 5.3.1 and 5.2.0

[pineman]

Hi!

Doing a simple HTTP.get("http://www.aplhealthcare.com.au") results in error reading from socket: Error Parsing data: HPE_INVALID_HEADER_TOKEN Invalid header value char (HTTP::SocketReadError) on 5.3.1 and 5.2.0, but NOT on 5.3.0. I'm using ruby 3.4.5.

I think it's due to the response's headers using \n instead of \r\n ("HTTP/1.1 301 Found\nDate: Fri Aug 1 23:02:05 2025\nServer: Redirector - NetRegistry Pty Ltd\nLocation: http://www.shop.livcor.com.au\nConnection: close\n\n\n", captured from parser.rb:29). But something fishy is going on because on 5.3.0 this works fine, probably due to the native llhttp?

Another example is https://bydenergy.com. Would appreciate some guidance on why it works on 5.3.0 but not 5.3.1 or 5.2.0. I believe it works on 5.1.1 too. Thanks.

[tarcieri]

The native llhttp seems like the most likely reason, and if so, the difference in behavior between the native and FFI version is something that's beyond our control