0003610: static function variables not "really" static

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Severity

Reproducibility

Date Submitted

Last Update

0003610

[Quercus]

major

always

07-27-09 10:33

08-27-09 11:39

Reporter

tlandmann

View Status

public

Assigned To

nam

Priority

normal

Resolution

fixed

Status

closed

Product Version

4.0.0

Summary

0003610: static function variables not "really" static

Description

The sample programm below prints the following (expected) in standard PHP 5.2.6:
0 1 2

In Quercus (non-compiled mode) it prints:
0 0 1

---------------------------

<?php

class class_1
{
    public static function method_1()
    {
        function_1();
    }

    public function method_2()
    {
        function_1();
    }
}

function function_1()
{
    static $value=0;
    echo $value++."\n";
}

function_1();
class_1::method_1();
$object=new class_1;
$object->method_2();

?>

---------------------------

I already kind of identified the problem:
"com.caucho.quercus.statement.StaticStatement:65" reads:
QuercusClass cls = env.getCallingClass();

This can't be fully correct because it returns "class_1" if the invocation of function_1() was made from the class - although the class really doesn't have anything to do with the static variable in the function.

---------------------------

QUERCUS DEVELOPERS PLEASE NOTE:
I almost spent 3 days on this bug, which completely breaks my adapted Drupal system because all the time parts of the CSS get lost (drupal_add_css() uses a static variable...).
This bug is so special that my only chance to find out what the problem was (and to invent a workaround) was to debug Resin on the Java level.

However, finding out how to do this was not easy. Netbeans just never stopped at my breakpoints, and I didn't have any idea, why. "http://wiki.caucho.com/IDE" [^] doesn't seem to be up-to-date any more. It took me ages finding out that I had to use config settings like this:
<jvm-arg>-Xdebug</jvm-arg>
<jvm-arg>-Xrunjdwp:transport=dt_socket,address=8998,server=y,suspend=n</jvm-arg>
instead of command line args to get it working.

A major step that I also took was recompiling Quercus with debug info, which also wasn't easy. I don't know if it was finally necessary but I still think so.
First I had to get all the elements needed, then I had to cope with the problem that the source code doesn't contain all classes needed to run Quercus.

To cut it short:
I could never have posted this bug without all this work because I didn't at all have it reproducible before I pinned the bug down in the debugger. I think if people go all this way to improve Resin, they help you a lot. So please also help us with these two things:
1: Offer a download with complete debug info in the .class files .
2: Write an up-to-date tutorial on how to debug Resin/Quercus.

Thanks. Keep up the good work.

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Notes
(0004108) nam 07-29-09 14:52	Thanks for the report! Our own Eclipse plugin for Quercus is in the works. Nevertheless, we can certainly update our docs on how to debug Quercus at the present moment. http://bugs.caucho.com/view.php?id=3614 [^]

(0004179) nam 08-27-09 11:39	php/0249

Issue History
Date Modified	Username	Field	Change
07-27-09 10:33	tlandmann	New Issue
07-29-09 14:50	nam	Status	new => assigned
07-29-09 14:50	nam	Assigned To	=> nam
07-29-09 14:52	nam	Note Added: 0004108
08-27-09 11:39	nam	Status	assigned => closed
08-27-09 11:39	nam	Note Added: 0004179
08-27-09 11:39	nam	Resolution	open => fixed
08-27-09 11:39	nam	Fixed in Version	=> 4.0.2

Mantis 1.0.0rc3[^]

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