GDB breakpoint on function arguments

Question

Can we set a GDB breakpoint on a function such that it will break into only if the function argument matches the value specified? Ex

int foo(int i) { return i*i; } int main() { foo(0); ................ foo(9); }

How do I set a breakpoint on foo only when the argument i of foo is 5?

blue112 · Accepted Answer · 2014-10-14 09:18:12Z

6

Sure, use "break if"

break foo if i == 5

If you have multiple variable if need to break on, just use classic if syntax :

break foo if i == 5 && j == 3

answered Oct 14, 2014 at 9:18

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5 Comments

Thanks! what if I have to match multiple arguments in foo(i,j,k) ?

break foo if i == 5 && j == 3, as simply as that.

@kartik: use the syntax familiar from C ... I.e. i == 5 && j == 3 (on occasion it is picky about parentheses being added and how).

@kartik No problem, be sure to validate the answer if it fits your needs.

@blue112 Yes waiting for 5 minute time limit to choose the answer.