py/mpstate: Make mp_pending_exception volatile.
py/mpstate: Make mp_pending_exception volatile.

It can change asynchronously.

torwag/micropython,adamkh/micropython,jmarcelino/pycom-micropython,adamkh/micropython,Timmenem/micropython,dhylands/micropython,Peetz0r/micropython-esp32,dinau/micropython,TDAbboud/micropython,martinribelotta/micropython,ryannathans/micropython,supergis/micropython,micropython/micropython-esp32,EcmaXp/micropython,Peetz0r/micropython-esp32,Peetz0r/micropython-esp32,hosaka/micropython,turbinenreiter/micropython,dmazzella/micropython,galenhz/micropython,matthewelse/micropython,xhat/micropython,ryannathans/micropython,ernesto-g/micropython,bvernoux/micropython,ruffy91/micropython,dinau/micropython,mhoffma/micropython,praemdonck/micropython,hosaka/micropython,martinribelotta/micropython,emfcamp/micropython,tuc-osg/micropython,emfcamp/micropython,infinnovation/micropython,galenhz/micropython,danicampora/micropython,redbear/micropython,matthewelse/micropython,HenrikSolver/micropython,PappaPeppar/micropython,supergis/micropython,matthewelse/micropython,chrisdearman/micropython,ruffy91/micropython,supergis/micropython,PappaPeppar/micropython,toolmacher/micropython,alex-march/micropython,infinnovation/micropython,pozetroninc/micropython,pfalcon/micropython,henriknelson/micropython,SHA2017-badge/micropython-esp32,dinau/micropython,tralamazza/micropython,jmarcelino/pycom-micropython,micropython/micropython-esp32,ganshun666/micropython,Timmenem/micropython,EcmaXp/micropython,selste/micropython,mianos/micropython,MrSurly/micropython-esp32,hiway/micropython,mpalomer/micropython,cwyark/micropython,selste/micropython,neilh10/micropython,pfalcon/micropython,MrSurly/micropython,mhoffma/micropython,EcmaXp/micropython,adafruit/circuitpython,ryannathans/micropython,alex-robbins/micropython,swegener/micropython,oopy/micropython,adafruit/micropython,mianos/micropython,dhylands/micropython,HenrikSolver/micropython,neilh10/micropython,bvernoux/micropython,mpalomer/micropython,pozetroninc/micropython,mianos/micropython,bvernoux/micropython,MrSurly/micropython,blazewicz/micropython,misterdanb/micropython,AriZuu/micropython,pfalcon/micropython,alex-robbins/micropython,chrisdearman/micropython,hosaka/micropython,ruffy91/micropython,cwyark/micropython,chrisdearman/micropython,tralamazza/micropython,misterdanb/micropython,galenhz/micropython,TDAbboud/micropython,dxxb/micropython,tobbad/micropython,hiway/micropython,pfalcon/micropython,trezor/micropython,turbinenreiter/micropython,adafruit/circuitpython,blazewicz/micropython,tuc-osg/micropython,blmorris/micropython,adafruit/micropython,kerneltask/micropython,galenhz/micropython,mhoffma/micropython,TDAbboud/micropython,ernesto-g/micropython,tobbad/micropython,alex-robbins/micropython,drrk/micropython,alex-march/micropython,jmarcelino/pycom-micropython,Peetz0r/micropython-esp32,HenrikSolver/micropython,galenhz/micropython,adafruit/circuitpython,blazewicz/micropython,Peetz0r/micropython-esp32,supergis/micropython,danicampora/micropython,redbear/micropython,lowRISC/micropython,dmazzella/micropython,MrSurly/micropython-esp32,AriZuu/micropython,matthewelse/micropython,swegener/micropython,HenrikSolver/micropython,adamkh/micropython,adafruit/circuitpython,MrSurly/micropython,puuu/micropython,deshipu/micropython,mpalomer/micropython,dhylands/micropython,blmorris/micropython,mhoffma/micropython,pfalcon/micropython,PappaPeppar/micropython,jmarcelino/pycom-micropython,puuu/micropython,dxxb/micropython,torwag/micropython,blazewicz/micropython,ruffy91/micropython,tobbad/micropython,selste/micropython,drrk/micropython,chrisdearman/micropython,MrSurly/micropython-esp32,redbear/micropython,swegener/micropython,hiway/micropython,ganshun666/micropython,MrSurly/micropython,SHA2017-badge/micropython-esp32,infinnovation/micropython,TDAbboud/micropython,hosaka/micropython,micropython/micropython-esp32,SHA2017-badge/micropython-esp32,lowRISC/micropython,SHA2017-badge/micropython-esp32,misterdanb/micropython,torwag/micropython,pramasoul/micropython,mpalomer/micropython,blmorris/micropython,bvernoux/micropython,martinribelotta/micropython,lowRISC/micropython,tuc-osg/micropython,ruffy91/micropython,drrk/micropython,misterdanb/micropython,kerneltask/micropython,praemdonck/micropython,dmazzella/micropython,alex-march/micropython,ernesto-g/micropython,neilh10/micropython,misterdanb/micropython,toolmacher/micropython,AriZuu/micropython,pramasoul/micropython,blmorris/micropython,dxxb/micropython,kerneltask/micropython,cwyark/micropython,tobbad/micropython,trezor/micropython,adafruit/circuitpython,chrisdearman/micropython,dmazzella/micropython,PappaPeppar/micropython,matthewelse/micropython,mpalomer/micropython,adafruit/micropython,oopy/micropython,deshipu/micropython,mhoffma/micropython,tralamazza/micropython,ganshun666/micropython,micropython/micropython-esp32,deshipu/micropython,hiway/micropython,dhylands/micropython,puuu/micropython,kerneltask/micropython,jmarcelino/pycom-micropython,danicampora/micropython,toolmacher/micropython,martinribelotta/micropython,trezor/micropython,neilh10/micropython,deshipu/micropython,dinau/micropython,henriknelson/micropython,danicampora/micropython,pozetroninc/micropython,praemdonck/micropython,tralamazza/micropython,turbinenreiter/micropython,turbinenreiter/micropython,selste/micropython,adamkh/micropython,danicampora/micropython,Timmenem/micropython,MrSurly/micropython,xhat/micropython,cwyark/micropython,MrSurly/micropython-esp32,Timmenem/micropython,puuu/micropython,lowRISC/micropython,alex-robbins/micropython,henriknelson/micropython,kerneltask/micropython,cwyark/micropython,AriZuu/micropython,tuc-osg/micropython,micropython/micropython-esp32,PappaPeppar/micropython,oopy/micropython,AriZuu/micropython,puuu/micropython,EcmaXp/micropython,blazewicz/micropython,dxxb/micropython,hosaka/micropython,mianos/micropython,redbear/micropython,xhat/micropython,adafruit/micropython,selste/micropython,emfcamp/micropython,pozetroninc/micropython,SHA2017-badge/micropython-esp32,ryannathans/micropython,oopy/micropython,ganshun666/micropython,deshipu/micropython,matthewelse/micropython,xhat/micropython,EcmaXp/micropython,Timmenem/micropython,trezor/micropython,blmorris/micropython,infinnovation/micropython,swegener/micropython,torwag/micropython,praemdonck/micropython,dinau/micropython,tuc-osg/micropython,turbinenreiter/micropython,henriknelson/micropython,ernesto-g/micropython,pramasoul/micropython,alex-march/micropython,drrk/micropython,tobbad/micropython,xhat/micropython,emfcamp/micropython,adafruit/micropython,lowRISC/micropython,supergis/micropython,praemdonck/micropython,hiway/micropython,martinribelotta/micropython,drrk/micropython,MrSurly/micropython-esp32,pramasoul/micropython,trezor/micropython,toolmacher/micropython,ryannathans/micropython,emfcamp/micropython,toolmacher/micropython,dhylands/micropython,infinnovation/micropython,pozetroninc/micropython,torwag/micropython,mianos/micropython,neilh10/micropython,HenrikSolver/micropython,redbear/micropython,pramasoul/micropython,alex-robbins/micropython,adamkh/micropython,swegener/micropython,TDAbboud/micropython,alex-march/micropython,bvernoux/micropython,ganshun666/micropython,dxxb/micropython,oopy/micropython,henriknelson/micropython,adafruit/circuitpython,ernesto-g/micropython