Bug #22495: UTF-32 strings with a byte 0x80 or more in the most significant position are reported as valid

• Status: Open
• Assignee: -
• Target version: -
• Backport: 3.3: REQUIRED, 3.4: REQUIRED, 4.0: REQUIRED

[mame (Yusuke Endoh)]

String#valid_encoding? returns true for UTF-32 sequences whose code point is 0x80000000 or more, when Ruby is built with gcc -O2.

"\xff\xff\xff\xff".force_encoding("UTF-32BE").valid_encoding? #=> true (expected: false)
"\x00\x00\x00\x80".force_encoding("UTF-32LE").valid_encoding? #=> true (expected: false)
"\xff\xff\xff\xff".force_encoding("UTF-32BE").ord             #=> 4294967295 (expected: ArgumentError)

@make_now_just (Hiroya Fujinami) found this and wrote the fix.

[mame (Yusuke Endoh)]

https://github.com/ruby/ruby/pull/19646