Regular Expresion - REPL - Guru Meditation Error

[mkharibalaji]

Hi Team,
I was trying to execute a RegEx using REPL in PyMakr and got the Meditation Error

Env : (sysname='LoPy', nodename='LoPy', release='1.2.2.b1', version='v1.8.6-317-g9ab243e on 2017-01-10', machine='LoPy with ESP32')

>>> import ure
>>> ure.match(b'^INFO( )+(.+)$','INFO {"server_id":"1ec445b504f4edfb4cf7927c707dd717","version":"0.6.6","go":"go1.4.2","host":"0.0.0.0","port":4222,"auth_required":false,"ssl_required":false,"max_payload":1048576}').group(0)
Guru Meditation Error of type StoreProhibited occurred on core  0. Exception was unhandled.
Register dump:
PC      : 0x4008832d  PS      : 0x00060031  A0      : 0x80086fff  A1      : 0x3ffc0790  
A2      : 0x3ffc5105  A3      : 0x3ffec2e0  A4      : 0x00000001  A5      : 0x3ffec250  
A6      : 0x000000aa  A7      : 0x3ffec200  A8      : 0x25000000  A9      : 0x00000000  
A10     : 0x0a000000  A11     : 0x00060023  A12     : 0x00060021  A13     : 0xb33f0000  
A14     : 0xb33fffff  A15     : 0x3ffec1e0  SAR     : 0x00000020  EXCCAUSE: 0x0000001d  
EXCVADDR: 0x00000008  LBEG    : 0x4000c2e0  LEND    : 0x4000c2f6  LCOUNT  : 0x00000000  

Backtrace: 0x4008832d:0x3ffc0790 0x40086fff:0x3ffc07b0 0x4008591e:0x3ffc07d0 0x40087d90:0x3ffc07f0 0x400812dd:0x3ffc0800

Rebooting...
ets Jun  8 2016 00:22:57

rst:0x3 (SW_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0x00
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:QIO, clock div:2
load:0x3fff9010,len:8
load:0x3fff9018,len:248
load:0x40078000,len:4072
load:0x4009f000,len:940
entry 0x4009f1ec

Thanks & regards,
Hari

[abilio]

@pod32, this was just a minimalistic example that triggers the guru. Unfortunately, we've been busy dealing with other parts of the firmware, and unable to find the root cause of this bug.

[pod32]

Have you tried to replace it by something like "\s{30}"?

[mkharibalaji]

@robert-hh @abilio When can we expect a fix for this issue ?

[robert-hh]

A similar error was discussed in the original Micropython community here:
https://github.com/micropython/micropython/issues/2451
The problem is not solved yet, as far as I know.

[abilio]

@mkharibalaji, I narrowed it down to this test:

The next example will make it break:

import ure
ure.match(b'^( )+$','                                                   ') # this will break

But this won't: (I just removed a whitespace)

import ure
ure.match(b'^( )+$','                                                  ')

It seems it has something to do with the length of the parameter.

Thank you very much for you're report. We'll be looking into it.