Doc #79675 [NEW]: Incorrect docs for array_key_exists opcode

From: paul at namepros dot com Operating system: Linux 5.4.0 PHP version: 7.4.6 Package: Documentation problem Bug Type: Documentation Problem Bug description:Incorrect docs for array_key_exists opcode Description: ------------ --- From manual page: https://php.net/migration74.other-changes --- On the aforementioned manual page, I read the following: > A specialized VM opcode for the array_key_exists() function has been added, which improves performance of this function if it can be statically resolved. In namespaced code, this may require writing \array_key_exists() or explicitly importing the function. This confirmed my assumption that use array_key_exists; should be a valid way to ensure that this new optimization is utilized in namespaced code. However, I was surprised to find that it doesn't seem to work according to VLD. Here's namespace-less code: % php -dvld.active=1 -dvld.execute=0 -r 'array_key_exists(1, []);' Finding entry points Branch analysis from position: 0 1 jumps found. (Code = 62) Position 1 = -2 filename: Command line code function name: (null) number of ops: 3 compiled vars: none line #* E I O op fetch ext return operands ------------------------------------------------------------------------------------- 1 0 E > ARRAY_KEY_EXISTS ~0 1, <array> 1 FREE ~0 2 > RETURN null branch: # 0; line: 1- 1; sop: 0; eop: 2; out0: -2 path #1: 0, But here's what I get with a namespaced version with `use array_key_exists;`: % php -dvld.active=1 -dvld.execute=0 -r 'namespace a; use array_key_exists; array_key_exists(1, []);' Finding entry points Branch analysis from position: 0 1 jumps found. (Code = 62) Position 1 = -2 filename: Command line code function name: (null) number of ops: 5 compiled vars: none line #* E I O op fetch ext return operands ------------------------------------------------------------------------------------- 1 0 E > INIT_NS_FCALL_BY_NAME 'a%5Carray_key_exists' 1 SEND_VAL_EX 1 2 SEND_VAL_EX <array> 3 DO_FCALL 0 4 > RETURN null branch: # 0; line: 1- 1; sop: 0; eop: 4; out0: -2 path #1: 0, Not what I expected, but https://www.php.net/manual/en/language.namespaces.faq.php#language.namespaces.faq.shortname2 seems to confirm that this is the expected behavior. The only way to optimize function calls like array_key_exists and is_array in namespaced code appears to be to use the fully qualified name, e.g. \array_key_exists. Test script: --------------- <?php namespace a; use array_key_exists; array_key_exists(1, []); -- Edit bug report at https://bugs.php.net/bug.php?id=79675&edit=1 -- Fix committed: https://bugs.php.net/fix.php?id=79675&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=79675&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=79675&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=79675&r=needscript Try newer version: https://bugs.php.net/fix.php?id=79675&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=79675&r=support Expected behavior: https://bugs.php.net/fix.php?id=79675&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=79675&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=79675&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=79675&r=globals PHP version support discontinued: https://bugs.php.net/fix.php?id=79675&r=phptooold Daylight Savings: https://bugs.php.net/fix.php?id=79675&r=dst IIS Stability: https://bugs.php.net/fix.php?id=79675&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=79675&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=79675&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=79675&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=79675&r=mysqlcfg