Issue #19924 has been updated by nagachika (Tomoyuki Chikanaga). Backport changed from 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED to 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE ruby_3_2 482e1f573ee45ef562cc6d218ba26d44660f8e0a merged revision(s) 17b0643392749f45b7aacb64fc1c1bd704d42b4c. ---------------------------------------- Bug #19924: Character literal escaped \xFF stops parsing https://bugs.ruby-lang.org/issues/19924#change-105247 * Author: kddnewton (Kevin Newton) * Status: Closed * Priority: Normal * Backport: 3.0: REQUIRED, 3.1: REQUIRED, 3.2: DONE ---------------------------------------- When you have a character literal, you can have an escaped character. For things that don't actually need escaping, this works out to just returning the character itself. For example: ``` ruby ?\d # => "d" ``` This works for every codepoint in ASCII-8bit _except_ 0xFF. When that byte is hit, the entire parser will stop parsing and just return `nil`. ``` ruby eval(<<~RUBY) # encoding: ascii-8bit p ?\\\xFF puts "this will never be parsed" RUBY ``` If you try to parse it with `RubyVM::AbstractSyntaxTree`, it's clear the parser just stops: ``` ruby RubyVM::AbstractSyntaxTree.parse(<<~RUBY) # encoding: ascii-8bit p ?\\\xFF puts "this will never be parsed" RUBY # => (SCOPE@1:0-2:1 tbl: [] args: nil body: (VCALL@2:0-2:1 :p)) ``` -- https://bugs.ruby-lang.org/