Description:
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when i assign a value to a variable using the contents of some other variable probably it does not check for validity of variable name and assigns value to it.


Reproduce code:
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error_reporting(E_ALL);
$test= 111 ;
$$test="This Should Not Be Allowed";
echo $$test;


Expected result:
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should be a parse error because a variable name is an integer

Actual result:
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This Should Not Be Allowed