Bug in mbed. Due to the call of printf inside mbed-os during interrupt (when program crashes)

Mbed OS
1

It is clear that when an interrupt happen due to a segmentation fault or any other problem inside your code, this function inside mbed-os fails

mbed_error_printf("\n++ MbedOS Fault Handler ++\n\nFaultType: "); (inside mbed_fault_handler.cpp)

Why?
Because printf is not allowed by mbedos…
It is silly that printf is not allowed but mbedos try to use it …

It has been like that for a long time … no one report it or try to fix it I think (not sure).
mbed_error_printf must be able to write to serial port even if it is inside an interrupt. As it is a fatal message … mbed shouldn’t care about anything else.

Due to this problem, I never can get a crash report.

I hope I explained well.

Note: NUCLEO_L476RG. Mbed-OS from the online IDE(latest)

2

You can’t use any operation that requires a mutex lock within an ISR context. It’s not allowed by Mbed for a variety of reasons.

I suggest that, instead, you use the interrupt to set a flag that is then serviced from a different thread.

Hope that helps,
Adam

3

@amitchone we already discus about that but he probably means another problem. See Serial interrupt not cleared after the interrupt?

BR, Jan

5

Again you didn’t understand the question either.
It is not about using serial in my code. It is mbed itself fails to give you a fatal report (hard fault)

6

Maybe you need to read it twice before reply, because I not wrote it to you but to Adam to show him that you were thinking something else and that we were already discussing it.
So sorry I want to help you. Nevermind.

BR, Jan

8

That kind of attitude goes nowhere towards getting people to help you, so count me out.