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Can a GDB breakpoint be set programmatically?
Can a GDB breakpoint be set programmatically?
I’d like to emulate the behavior of assert() in IAR. If the debugger is connected, then a breakpoint is automatically “generated” when an assert() fails, and you can inspect code and/or call stacks. This probably requires setting up an exception, but I’m not sure how to proceed.
Hello,
Thank you for reaching out to us!
It depends on the target, but usually a failed assert will call the abort function. GDB users can create a breakpoint in the abort function to catch failed asserts by executing the following GDB command while debugging:
br abort
Developers can also use target specific instructions to cause GDB to suspend execution and allow the inspection of the program state. For example, the RL78 uses the brk instruction for this:
foo.c :
__asm("brk");
Please let us know if we can be of further assistance.
__
Best regards,
The Open Source Tools Team
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jltrahan -
This is for the RX, so I would use the __builtin_rx_brk() function. However, the BRK instruction simply “generates” an exception, which is what I was alluding to in my question. Does anyone have an example of setting this up?
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Hello,
Please consider the following:
test.c:
#include
int main() {
int x = 12;
__builtin_rx_brk();
x = 13;
assert(x == 12);
return 0;
}The commands below illustrate both approaches:
rx-elf-gcc -msim test.c -g
rx-elf-gdb a.out -ex “target sim” -ex “load” -ex “br abort” -ex “run” -ex “bt” -ex “c” -ex “bt”
Explanation:
After creating the executable from the source file, we launch a debug session and insert a breakpoint into the abort() function. When we begin execution, the debugger will first stop at the BRK instruction.
If we issue the continue command, the debugger stops at the abort() breakpoint.
In both cases, the program state can be inspected: in our example we display the call stack.Please elaborate further if this behavior is not what you are looking for.
__
Best regards,
The Open Source Tools Team -
jltrahan -
That’s my problem: __builtin_rx_brk() (or the asm(“brk”); version) does NOT break… execution simply continues.
