Help confirming possible bug on SAMD21 EXTI

Hello everyone,

I would like to ask some help for confirming a possible bug on SAMD21 EXTI. Some times ago, I found a similar bug in SAML21 (see #6904 and #6932) In fact, one EXTI works fine but if you register at least 2 EXTIs, only the first one can be triggered. (Tested with tests/periph_gpio)

But after looking cpu/samd21/periph/gpio.c, I found out, SAML21 and SAMD21 GPIO drivers are copy/paste. So the same bug can also affect SAMD21.

Unfortunately, I don’t have the required hardware to confirm it. Can someone with a SAMD21-Xpro or SAMR21-Xpro board confirm the presence of this bug ?

Thanks a lot for your help !