HardFaultTrampoline now passes &mut ExceptionFrame #515
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In order to allow for a user provided HardFault handler to modify the exception frame (e.g. to return to a different PC) the signature for the function to be used with the
#[HardFault]
handler now has a&mut ExceptionFrame
instead of just a reference.Use case: we want to catch an exception, so we set some flag, run some code that might trigger a HardFault, update the flag in the handler, and return to the instruction after the one that caused the exception. We can then check the flag to see if an exception occurred or not. Key point is: to return to the instruction following the one that caused the exception, we want to modify the PC on the
ExceptionFrame
before loading EXC_RETURN onto the PC.