[Bug]: Debug session ends unexpectedly with the error "GDB exited unexpectedly"

[chentang16]

Description

When testing the Blinky reference example for STM32F746-Disc board, I set a breakpoint at a semihosting printf(). The debugger can pause correctly at the breakpoint. But when click run again, the debug session ends unexpectedly with the error "GDB exited unexpectedly" as shown in the screenshot:

CMSIS Solution extension: 1.60.1-141-gb542ed3
CMSIS Debugger extension: 1.1.1-main16-gbd3fcbd.0

Attach the reproducer blinky example here

BlinkyTest - Copy.zip

Steps to Reproduce

1. Build project
2. Select ST-Link@pyOCD as debugger
3. start debug session and run
4. execution stops at the line 86 (breakpoint) of blinky.c
5. click run again
6. debug session ends unexpectedly with the error shown above

Expected Behavior

No response

Additional Information

No response

[jreineckearm]

Looks like a duplicate of #242 and #159 which we unfortunately can only mitigate but not fully fix.

@chentang16 , can you please check if you have the following set in the dbgconf file: #242 (comment)

[chentang16]

I set the DbgMCU_APB1_Fz = 0x00000100; in my dbgconf file as shown below, but it doesn't fix the issue unfortunately:

[jreineckearm]

Can you try to freeze all peripherals? I don't know the example you are using, so it may be a different interrupt causing it. But even then, we saw problems in the past for very high frequent interrupts like from LCD displays.

[chentang16]

similar to #242 (comment), my blinky example also use the TIM14 as a time base source. But after I turn on the freeze for all register parts as shown below, the debug issue is still not resolved: