Description:
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Return of create_function() concat. with 'foo'.
But, when calling the function with the name of variable's value, only 'foo' is used...

Reproduce code:
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<?php

$a = 'foo'. create_function('', 'print "foo!";');

var_dump($a); // string(12) "foolambda_1"

function foo() { print 1; }

$a();         // Fatal error: Call to undefined function foo()

// foo() ?!


Expected result:
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Fatal error: Call to undefined function foolambda_1()

Actual result:
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string(12) "foolambda_1"

Fatal error: Call to undefined function foo()