Description:
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I've come across one character that doesn't transliterate correctly with iconv() with the "TRANSLIT" option on Linux.

On Windows, it works - on every Linux build (PHP 5.3, 5.4, 5.5, 5.6, 7.0 and HHVM) it fails for this one character.

Unfortunately, this particular character is a normal character in Danish language, and the sites we build are in Danish.

The expected result posted below is that from a Windows build - the actual result is the erroneous result from a Linux build.

I know that libiconv is largely unmaintained, so maybe there is nothing to be done about this - a comment in the manual says to use mbstring and intl instead, but intl isn't a standard extension, and mbstring doesn't seem to have this feature?

I can work around this particular case, of course, by replacing ø and Ø myself first, but I find it problematic that this common operation isn't otherwise supported (or doesn't work) in PHP.


Test script:
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<?php

// https://gist.github.com/mindplay-dk/9b2fa55ba5f08ab0b9308295f936cd41

$string = 'æøå'; // HEX: c3 a6 c3 b8 c3 a5

$clean = iconv('UTF-8', 'ASCII//TRANSLIT', $string);

var_dump($clean); // "aeoa" on Windows, "ae?a" on Linux???


Expected result:
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string(4) "aeoa"

Actual result:
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string(4) "ae?a"