Memory leak in attachSystemInterrupt?

Continuing the discussion from Solid green/lockup after ~44 minutes:

I had a working application that used a timer, but when I went to turn my timer code into a C++ class, the app would freeze after a certain amount of time. Using the timer more frequently decreased the time before the lockup.

I started over and incrementally ended up with working code, the only difference I saw was moving attachSystemInterrupt(hal_irq_t irq, wiring_interrupt_handler_t handler) into the initialization instead of the timer start. Initially I was using a different callback depending on what mode my timer class was in. Looking at that code, it appears to allocate = new wiring_interrupt_handler_t(h);, but ignores the previous callback returned from HAL_Set_System_Interrupt_Handler.

I suspect this is a memory leak, and when allocation eventually failed explained why my app froze, the interrupt eventually called into nowhere. Is this correct?

As a workaround, I can set one handler, and dispatch from that depending on the mode of my timer.

Thanks for reporting this issue @mcarland. You are right about the memory leak. I created a GitHub issue for it.

Your workaround is good for now: create one handler and dispatch within in.