Description:
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If i use json_encode its truncates the string on an unexpected char like the german umlauts.

Reproduce code:
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<?
$x = new stdClass();
$x->val = 'R?ck';
echo json_encode('R?ck');
echo json_encode($x);


Expected result:
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"R?ck"{"val":"R?ck"}

Actual result:
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"R"{"val":"R"}