From: matt dot flaherty at hildebrand dot co dot uk
Operating system: SUSE LINUX 10.0 (i586)
PHP version: 4.4.2
PHP Bug Type: Reproducible crash
Bug description: segfault when testing property of an overloaded class in
switch a statement
Description:
------------
Apologies in advance if this turns out to be user error, but it seems odd
to me. A segmentation fault occurs when evaluating in a switch statement
an instance property of an overloaded class with which has a __get()
method. It does not matter whether the evaluated property is native to the
instance or overloaded. Also, native and overloaded properties on an
overloaded class instance don't like to be passed by reference.
If you change the switch statements to cast the argument to (string), as
in "switch ((string)$decorator->bar) {" (a memory copy), then the expected
result occurs. If you leave either of the switch statements alone there is
a crash. Interestingly, with both of the switch statements "fixed" and the
block uncommented that calls function reverse_me, the output looks like
this:
----%<----
I can see that the value of bar is 'bar' and the value of myVar is
'mine'.
I've tested === and that worked okay.
So did ==.
subst function is okay too.
Fatal error: Only variables can be passed by reference in
/srv/www/htdocs/seagull/www/crash.php on line 54
----%<----
This is a native property on the instance so I can't understand why
passing by reference is bad. Turning off overloading produces the expected
result there, which is this:
----%<----
I can see that the value of bar is '' and the value of myVar is 'mine'.
I've tested === and that worked okay.
So did ==.
subst function is okay too.
Just passed by myVar by reference and reversed the string. The value is
now enim
I am not expecting a switch statemtent on bar to segfault.
Switch says the value of bar is not 'bar'. It's 'baz'.
I am not expecting a switch statemtent on myVar to segfault.
Switch says the value of myVar is not 'mine'. It's 'yours'.
----%<----
I have observed this behaviour in php 4.4.0 and 4.4.2. Very strange.
Reproduce code:
---------------
http://www.jellybee.co.uk/overload_fault.txt
Expected result:
----------------
I can see that the value of bar is 'bar' and the value of myVar is
'mine'.
I've tested === and that worked okay.
So did ==.
subst function is okay too.
I am not expecting a switch statemtent on bar to segfault.
Switch says the value of bar is not 'bar'. It's 'baz'.
I am not expecting a switch statemtent on myVar to segfault.
Switch says the value of myVar is not 'mine'. It's 'yours'.
Actual result:
--------------
Last few lines of Apache2 strace...
open("/srv/www/htdocs/seagull/www/crash.php", O_RDONLY) = 35
fstat64(35, {st_mode=S_IFREG|0644, st_size=2110, ...}) = 0
fstat64(35, {st_mode=S_IFREG|0644, st_size=2110, ...}) = 0
lseek(35, 0, SEEK_CUR) = 0
lseek(35, 0, SEEK_SET) = 0
read(35, "<?php\nclass Decorator_Foo {\n "..., 8192) = 2110
brk(0x8045f000) = 0x8045f000
read(35, "", 8192) = 0
close(35) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
chdir("/srv/www") = 0
rt_sigaction(SIGSEGV, {SIG_DFL}, {SIG_DFL}, 8) = 0
kill(18058, SIGSEGV) = 0
sigreturn() = ? (mask now [])
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
--
Edit bug report at http://bugs.php.net/?id=36234&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=36234&r=trysnapshot44
Try a CVS snapshot (PHP 5.1):
http://bugs.php.net/fix.php?id=36234&r=trysnapshot51
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=36234&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=36234&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=36234&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=36234&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=36234&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=36234&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=36234&r=support
Expected behavior: http://bugs.php.net/fix.php?id=36234&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=36234&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=36234&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=36234&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=36234&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=36234&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=36234&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=36234&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=36234&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=36234&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=36234&r=mysqlcfg
