[BUG] [CRASH] Segmentation fault in \Phalcon\Mvc\View\Engine\Volt\Compiler::expression()

Very simple test case:

$c = new \Phalcon\Mvc\View\Engine\Volt\Compiler();
$c->expression(array('type' => 275));

Backtrace:

Program terminated with signal 11, Segmentation fault.
#0  0x00007f2e56772609 in phalcon_concat_vsv (result=0x7fff1f121e68, op1=0x0, op2=0x7f2e5698c19d " !== ", op2_len=5, op3=0x0, self_var=0, tsrm_ls=0x31dd850) at /home/vladimir/workspace/cphalcon/build/64bits/phalcon.c:8582
8582            if (Z_TYPE_P(op1) != IS_STRING) {
(gdb) bt
#0  0x00007f2e56772609 in phalcon_concat_vsv (result=0x7fff1f121e68, op1=0x0, op2=0x7f2e5698c19d " !== ", op2_len=5, op3=0x0, self_var=0, tsrm_ls=0x31dd850) at /home/vladimir/workspace/cphalcon/build/64bits/phalcon.c:8582
#1  0x00007f2e568cf3ad in zim_Phalcon_Mvc_View_Engine_Volt_Compiler_expression (ht=1, return_value=0x7f2e60423930, return_value_ptr=0x7f2e603e8100, this_ptr=0x7f2e60421b38, return_value_used=0, tsrm_ls=0x31dd850)
    at /home/vladimir/workspace/cphalcon/build/64bits/phalcon.c:75705
#2  0x00007f2e5696bcd5 in phalcon_execute_internal (execute_data_ptr=0x7f2e603e81d8, fci=0x0, return_value_used=0, tsrm_ls=0x31dd850) at /home/vladimir/workspace/cphalcon/build/64bits/phalcon.c:100393
#3  0x0000000000a74f4f in zend_do_fcall_common_helper_SPEC (execute_data=0x7f2e603e81d8, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/Zend/zend_vm_execute.h:552
#4  0x0000000000a759b2 in ZEND_DO_FCALL_BY_NAME_SPEC_HANDLER (execute_data=0x7f2e603e81d8, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/Zend/zend_vm_execute.h:685
#5  0x0000000000a7424e in execute_ex (execute_data=0x7f2e603e81d8, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/Zend/zend_vm_execute.h:363
#6  0x0000000000a74333 in zend_execute (op_array=0x7f2e604229e8, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/Zend/zend_vm_execute.h:388
#7  0x0000000000a2ec68 in zend_execute_scripts (type=8, tsrm_ls=0x31dd850, retval=0x0, file_count=3) at /tmp/php-build/source/5.5.4/Zend/zend.c:1318
#8  0x000000000096f9ec in php_execute_script (primary_file=0x7fff1f124690, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/main/main.c:2489
#9  0x0000000000aef369 in do_cli (argc=2, argv=0x31dd770, tsrm_ls=0x31dd850) at /tmp/php-build/source/5.5.4/sapi/cli/php_cli.c:994
#10 0x0000000000af09a0 in main (argc=2, argv=0x31dd770) at /tmp/php-build/source/5.5.4/sapi/cli/php_cli.c:1378

Affects both 1.2.x and 1.3.0