GDB: Python Exception <class 'TypeError'>: exceptions must derive from BaseException

[DanielEScherzer]

Description

The following code:

<?php

$a = 1;
var_dump( $a );

in /var/www/html/test.php. when run with GDB:

(gdb) set print pretty on
(gdb) break /usr/src/php/ext/standard/var.c:105
Breakpoint 1 at 0x4b6130: file /usr/src/php/ext/standard/var.c, line 105.
(gdb) run /var/www/html/test.php
Starting program: /usr/local/bin/php /var/www/html/test.php
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Breakpoint 1, php_var_dump (struc=0x7ffff54140f0, level=1) at /usr/src/php/ext/standard/var.c:113
113             if (level > 1) {
(gdb) p *struc

Where var.c:113 at the time was

php-src/ext/standard/var.c

Line 113 in c65e042

if (level > 1) {

Resulted in this output:

$1 = Python Exception <class 'TypeError'>: exceptions must derive from BaseException
Python Exception <class 'TypeError'>: exceptions must derive from BaseException
{
  value = {
    lval = 1,
...
}

But I expected this output instead:

No errors

PHP Version

PHP 8.4-dev

[cmb69]

While I don't understand why PHP would throw a TypeError here, the error message is certainly not related to nice elephpants, but rather to nasty reptiles. ;)

[DanielEScherzer]

While I don't understand why PHP would throw a TypeError here, the error message is certainly not related to nice elephpants, but rather to nasty reptiles. ;)

Its not a PHP type error, its a Python one - I boiled it down to a minimal reproduction case, but I was getting a lot of these (I just started using GDB for PHP)

I see this is tagged as needing feedback - what more can I provide?

[cmb69]

The question is: why do you get a Python error when running/debugging PHP code? I think there is something wrong with your setup.

[DanielEScherzer]

The question is: why do you get a Python error when running/debugging PHP code? I think there is something wrong with your setup.

I believe it is because the GDB stuff is written in python, see https://github.com/php/php-src/blob/1ce07b0957c9323e93c45d0a83c0133aa177a911/scripts/gdb/php_gdb.py

[nielsdos]

The error likely comes from this line:

php-src/scripts/gdb/php_gdb.py

Line 304 in 1ce07b0

raise "Could not find zend_types.h: symbol zend_gc_refcount not found"

You can't raise a string.
@DanielEScherzer Are you using a release build? That could explain why it can't find the symbol required.

[DanielEScherzer]

The error likely comes from this line:

php-src/scripts/gdb/php_gdb.py

Line 304 in 1ce07b0

raise "Could not find zend_types.h: symbol zend_gc_refcount not found"

You can't raise a string.
@DanielEScherzer Are you using a release build? That could explain why it can't find the symbol required.

I didn't think I was, but running ./configure --enable-debug and then re-make-ing and trying again fixed the issue. I guess then the attempted error makes sense, but the actual error (from raising a string) is problematic and should still be fixed

[nielsdos]

Yeah, I'll fix it. Looks like it's just on the master branch.

[cmb69]

I believe it is because the GDB stuff is written in python, see https://github.com/php/php-src/blob/1ce07b0957c9323e93c45d0a83c0133aa177a911/scripts/gdb/php_gdb.py

Ah, I hadn't noticed this yet.