Bug #54039 [NEW]: use() of static variables in lambda functions can break staticness

From: Operating system: Windows XP PHP version: 5.3.5 Package: Scripting Engine problem Bug Type: Bug Bug description:use() of static variables in lambda functions can break staticness Description: ------------ Let an ordinary function declare a static local variable, and let it also define an anonymous function that uses that static variable. It can happen that the static variable no longer retains its value across calls to the ordinary function; i.e., it loses that static property. It seems to be limited to situations where the anonymous function is defined before the static variable has had its value changed. Test script: --------------- function test_1() { static $v = 0; ++$v; echo "Outer function increments \$v to $v\n"; $f = function()use($v) { echo "Inner function reckons \$v is $v\n"; }; return $f; } echo "\nIncrement static variable, then use it in anonymous function definition:\n"; $f = test_1(); $f(); $f = test_1(); $f(); function test_2() { static $v = 0; $f = function()use($v) { echo "Inner function reckons \$v is $v\n"; }; ++$v; echo "Outer function increments \$v to $v\n"; return $f; } echo "\nUse static variable in anonymous function definition, then increment it:\n"; $f = test_2(); $f(); $f = test_2(); $f(); Expected result: ---------------- Increment static variable, then use it in anonymous function definition: Outer function increments $v to 1 Inner function reckons $v is 1 Outer function increments $v to 2 Inner function reckons $v is 2 Use static variable in anonymous function definition, then increment it: Outer function increments $v to 1 Inner function reckons $v is 0 Outer function increments $v to 2 Inner function reckons $v is 1 Actual result: -------------- Increment static variable, then use it in anonymous function definition: Outer function increments $v to 1 Inner function reckons $v is 1 Outer function increments $v to 2 Inner function reckons $v is 2 Use static variable in anonymous function definition, then increment it: Outer function increments $v to 1 Inner function reckons $v is 0 Outer function increments $v to 1 Inner function reckons $v is 0 -- Edit bug report at http://bugs.php.net/bug.php?id=54039&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=54039&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=54039&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=54039&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=54039&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=54039&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=54039&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=54039&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=54039&r=needscript Try newer version: http://bugs.php.net/fix.php?id=54039&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=54039&r=support Expected behavior: http://bugs.php.net/fix.php?id=54039&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=54039&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=54039&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=54039&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=54039&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=54039&r=dst IIS Stability: http://bugs.php.net/fix.php?id=54039&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=54039&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=54039&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=54039&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=54039&r=mysqlcfg