topic Re: Cannot debug in a static library in MCUXpresso IDE

Cannot debug in a static library

ruslan1 — Wed, 04 Jan 2023 10:26:00 GMT

I try to debug my application that runs on LPC11C24 chip using MCUxpresso 11.5. The application uses a static library that encapsulates some functions. Both application and the library are in Debug mode The debug level is Maximum (-g3) for both of them.

The very simplified code looks like the following:

int main(void) { while(1) { lib_func(); } } // my_lib.a int lib_func(void) { some_func(); // here the debug fails } int some_func(void) { }

I can debug the application but for some reason what I enter the function and try to step it with F6 the debugging failed with error:

Failed to execute MI command:
-exec-next 1
Error message from debugger back end:
Cannot find bounds of current function

That what I see in the debug tab:

As for me it looks that the library has no debug symbols.

The application MCU compiler options:

-DDEBUG -D__CODE_RED -D__USE_CMSIS=CMSISv2p00_LPC11xx -D__REDLIB__ -I"F:\source\my_lib\inc" -O0 -g3 -Wall -c -fmessage-length=0 -fno-builtin -ffunction-sections -fdata-sections -fmerge-constants -fmacro-prefix-map="$(<D)/"= -mcpu=cortex-m0 -mthumb -D__REDLIB__ -fstack-usage -specs=redlib.specs

The application MCU Linker options:

-nostdlib -L"F:\source\my_lib\Debug" -Xlinker -Map="my_app.map" -Xlinker --gc-sections -mcpu=cortex-m0 -mthumb -T "my_app.ld" -L ../linker

The library MCU compiler options:

-DDEBUG -D__CODE_RED -D__USE_CMSIS=CMSISv2p00_LPC11xx -D__REDLIB__ -O0 -g3 -Wall -c -fmessage-length=0 -fno-builtin -ffunction-sections -fdata-sections -fmerge-constants -fmacro-prefix-map="$(<D)/"= -mcpu=cortex-m0 -mthumb -D__REDLIB__ -fstack-usage -specs=redlib.specs

Re: Cannot debug in a static library

ErichStyger — Wed, 04 Jan 2023 12:45:39 GMT

I don't see anything wrong, but maybe you could share your .a file?

The debugger message looks like a problem in gdb with that 'empty' library function. Have you maybe tried the same with IDE 11.6.1 as it comes with a newer GNU toolchain and debugger?

Re: Cannot debug in a static library

ruslan1 — Tue, 17 Jan 2023 10:37:49 GMT

Ok, it looks that debugger just steps to some space out of the application. I don't understand why. It stops on any breakpoint (in the application or in the library) but when I press F6 it just jumps out (see the red arrow on the screenshot).

Re: Cannot debug in a static library

ruslan1 — Tue, 17 Jan 2023 10:41:44 GMT

I've upgraded the IDE to the last version but that didn't help.

Re: Cannot debug in a static library

ErichStyger — Wed, 18 Jan 2023 06:41:36 GMT

it would be certainly helpful if you could provide a minimal reproducible example.

Re: Cannot debug in a static library

lpcxpresso_supp — Fri, 20 Jan 2023 13:06:25 GMT

0x1FFF_0042 is somewhere in the memory area reserved for boot ROM. If you're trying to Step Over (F6) when core is stopped there, failure of "-exec-next 1" is somehow expected... GDB does not have the appropriate debug information to cover the boot ROM code area, so it cannot step over anything.

Without having any kind of knowledge about your app, I cannot say what could be wrong... I recommend inspecting the Disassembly view to understand what makes the debugger end-up in the boot ROM area. Also, you could activate Instruction Stepping in Debug view and single step (F5) instructions. Is the expected function/point reached eventually?

Also, is there any chance there's some kind of watchdog resetting the MCU when stepping? Or maybe there's something else causing a reset.

Regards,
MCUXpresso IDE Support