Fuzzer `php-fuzz-execute` crashes at `zend_gc_delref`

[gal1ium]

Description

The following code:

<?php 
    $var1[][]=$l;
    set_error_handler(
        function()use(&$var1){
            $var1=0;
        }
    );
    $var1[0].=0;

Resulted in this crashing status by the fuzzing driver php-fuzz-execute:

==961978== ERROR: libFuzzer: deadly signal

#0  zend_gc_delref () at Zend/zend_types.h:1371
#1  i_zval_ptr_dtor () at Zend/zend_variables.h:44
#2  concat_function () at Zend/zend_operators.c:2085
#3  zend_binary_op () at Zend/zend_execute.c:1635
#4  ZEND_ASSIGN_DIM_OP_SPEC_CV_CONST_HANDLER () at Zend/zend_vm_execute.h:42722
#5  fuzzer_execute_ex () at sapi/fuzzer/fuzzer-execute-common.h:59
#6  zend_execute () at Zend/zend_vm_execute.h:64385
#7  fuzzer_do_request_from_buffer () at sapi/fuzzer/fuzzer-sapi.c:274
#8 LLVMFuzzerTestOneInput () at sapi/fuzzer/fuzzer-execute.c:27

PHP Version

dbabbe180b157eeaac5002276667f1f56f0b4def 2025-06-10 22:35:56+0200

Operating System

Linux

[nielsdos]

Duplicate of #16726