Can gdb be used to backtrace when exceptions are c

问题:

I have just started using c++ exceptions and want to get it right. What I have in mind is to generate some sort of backtrace information when exceptions are caught. Initially I had ideas similar to Call-stack for exceptions in C++ but eventually figured out that's not quite good.

I have also read How to generate a stacktrace when my gcc C++ app crashes but do not want to add more complexity to my current project. Since, I only need the backtracing when in debug mode, I was hoping I could be using gdb for that purpose.

My strategy has been to insert breakpoint in the catch block and then go up through the call stack to exactly pinpoint why the exception was thrown in the first place (or what caused it)? Unfortunatly, I cannot seem to be able to do this since when gdb reaches the breakpoint, it clears the call stack and I can only see main (that's where I catch). Is this supposed to happen or am I doing something wrong here?

Edit: I just like to summarize the methods here for other folks:

1st Method (by paulsm4). Set a catchpoint via catch throw for catching on throw or catch catch for catching on catch! Then call backtrace

2nd Method (by aschepler) Set a breakpoint on __cxa_throw and then backtrace

3rd Method (in Qt Creator -- if you happen to use) You can easily set a breakpoint on throw or catch!

Edit_2: Using Qt Creator debugger, it seems that setting a breakpoint on __cxa_begin_catch is also an equivalent to catch catch :)

回答1:

This this:

http://sourceware.org/gdb/onlinedocs/gdb/Set-Catchpoints.html

You can use catchpoints to cause the debugger to stop for certain kinds of program events, such as C++ exceptions or the loading of a shared library. Use the catch command to set a catchpoint.

So the answer should be "yes", and it should avoid the problems with the two links you cited.

Please post back if it helped! Personally, I've never tried this GDB feature myself :)

回答2:

Summary of answers from the comments:

1st Method (by paulsm4). Set a catchpoint via catch throw for catching on throw or catch catch for catching on catch! Then call backtrace

2nd Method (by aschepler) Set a breakpoint on __cxa_throw and then backtrace

3rd Method (in Qt Creator -- if you happen to use) You can easily set a breakpoint on throw or catch!

Using Qt Creator debugger, it seems that setting a breakpoint on __cxa_begin_catch is also an equivalent to catch catch