C++ display stack trace on exception

Question

I want to have a way to report the stack trace to the user if an exception is thrown. What is the best way to do this? Does it take huge amounts of extra code?

To answer questions:

I'd like it to be portable if possible. I want information to pop up, so the user can copy the stack trace and email it to me if an error comes up.

Answer 1

Poppy can gather not only the stack trace, but also parameter values, local variables, etc. - everything leading to the crash.

Answer 2

Andrew Grant's answer does not help getting a stack trace of the throwing function, at least not with GCC, because a throw statement does not save the current stack trace on its own, and the catch handler won't have access to the stack trace at that point any more.

The only way - using GCC - to solve this is to make sure to generate a stack trace at the point of the throw instruction, and save that with the exception object.

This method requires, of course, that every code that throws an exception uses that particular Exception class.

Update 11 July 2017: For some helpful code, take a look at cahit beyaz's answer, which points to http://stacktrace.sourceforge.net - I haven't used it yet but it looks promising.

Answer 3

If you are using Boost 1.65 or higher, you can use boost::stacktrace:

#include <boost/stacktrace.hpp>

// ... somewhere inside the bar(int) function that is called recursively:
std::cout << boost::stacktrace::stacktrace();

Answer 4

AFAIK libunwind is quite portable and so far I haven't found anything easier to use.

Answer 5

I recommend http://stacktrace.sourceforge.net/ project. It support Windows, Mac OS and also Linux

Answer 6

I have a similar problem, and though I like portability, I only need gcc support. In gcc, execinfo.h and the backtrace calls are available. To demangle the function names, Mr. Bingmann has a nice piece of code. To dump a backtrace on an exception, I create an exception that prints the backtrace in the constructor. If I were expecting this to work with an exception thrown in a library, it might require rebuilding/linking so that the backtracing exception is used.

/******************************************
#Makefile with flags for printing backtrace with function names
# compile with symbols for backtrace
CXXFLAGS=-g
# add symbols to dynamic symbol table for backtrace
LDFLAGS=-rdynamic
turducken: turducken.cc
******************************************/

#include <cstdio>
#include <stdexcept>
#include <execinfo.h>
#include "stacktrace.h" /* https://panthema.net/2008/0901-stacktrace-demangled/ */

// simple exception that prints backtrace when constructed
class btoverflow_error: public std::overflow_error
{
    public:
    btoverflow_error( const std::string& arg ) :
        std::overflow_error( arg )
    {
        print_stacktrace();
    };
};


void chicken(void)
{
    throw btoverflow_error( "too big" );
}

void duck(void)
{
    chicken();
}

void turkey(void)
{
    duck();
}

int main( int argc, char *argv[])
{
    try
    {
        turkey();
    }
    catch( btoverflow_error e)
    {
        printf( "caught exception: %s\n", e.what() );
    }
}

Compiling and running this with gcc 4.8.4 yields a backtrace with nicely unmangled C++ function names:

stack trace:
 ./turducken : btoverflow_error::btoverflow_error(std::string const&)+0x43
 ./turducken : chicken()+0x48
 ./turducken : duck()+0x9
 ./turducken : turkey()+0x9
 ./turducken : main()+0x15
 /lib/x86_64-linux-gnu/libc.so.6 : __libc_start_main()+0xf5
 ./turducken() [0x401629]