A C++ function that produces a stack backtrace with demangled function & method names.

stacktrace.cxx

#include <execinfo.h>  // for backtrace
#include <dlfcn.h>     // for dladdr
#include <cxxabi.h>    // for __cxa_demangle

#include <string>
#include <sstream>

// This function produces a stack backtrace with demangled function & method names.
std::string Backtrace(int skip = 1)
{
	void *callstack[128];
	const int nMaxFrames = sizeof(callstack) / sizeof(callstack[0]);
	char buf[1024];
	int nFrames = backtrace(callstack, nMaxFrames);
	char **symbols = backtrace_symbols(callstack, nFrames);

	std::ostringstream trace_buf;
	for (int i = skip; i < nFrames; i++) {
		Dl_info info;
		if (dladdr(callstack[i], &info)) {
			char *demangled = NULL;
			int status;
			demangled = abi::__cxa_demangle(info.dli_sname, NULL, 0, &status);
			snprintf(buf, sizeof(buf), "%-3d %*0p %s + %zd\n",
					 i, 2 + sizeof(void*) * 2, callstack[i],
					 status == 0 ? demangled : info.dli_sname,
					 (char *)callstack[i] - (char *)info.dli_saddr);
			free(demangled);
		} else {
			snprintf(buf, sizeof(buf), "%-3d %*0p\n",
					 i, 2 + sizeof(void*) * 2, callstack[i]);
		}
		trace_buf << buf;

		snprintf(buf, sizeof(buf), "%s\n", symbols[i]);
		trace_buf << buf;
	}
	free(symbols);
	if (nFrames == nMaxFrames)
		trace_buf << "[truncated]\n";
	return trace_buf.str();
}

A C++ function that will produce a stack trace with demangled function and method names.

Awesome! YMMD ^^

Glad you found it useful. :)

Thanks for this very useful gist!
If you are linking your binary using GNU ld you need to add --export-dynamic or most of your symbols will just be resolved to the name of the binary.

Good point @dholm, thank you.

I'm wanting to use a modification of this in some commercial software (saves a bit of re-inventing). What copyright and license is this released with?

@dgotwisner In the past I've favored the BSD 2-clause license, so I've updated the gist to reflect this. I hope this works for you!

I am not getting correct function names of a C++ program.

@pabitrad, this is probably due the missing -export-dynamic GCC flag.
Trying rebuilding with : g++ -g -fpic -std=c++14 -export-dynamic Main.cpp -ldl -o Main.

That did it for me. It works like a charm, thanks @fmela! 😉

pabitrad's problem is due to an error in the code: In snprintf format string replace '%*0p' by '%0*p'. That will fix it.

Thanks for this useful piece of code! We changed it a little to return a std::vector instead of a string buffer.
https://github.com/bareos/bareos

Awesome! It would be better if it supported pretty print c++ method name.

__ZN4wuta12WTFaceModule14rendererUpdateENS_11RenderSceneENS_10RenderModeERNS_10InputFrameEiiii

wuta::WTFaceModule::rendererUpdate(wuta::RenderScene, wuta::RenderMode, wuta::InputFrame&, int, int, int, int)

Like what c++filt do

@xiaozhuai, it should be de-mangling the names. Would you share your compiler, compiler flags, and linker flags here?

@fmela Android NDK 15 with clang.

-D__ANDROID_API__=21 -g -DANDROID -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes  -mfloat-abi=softfp -mfpu=vfpv3-d16 -fno-integrated-as -mthumb -mfpu=neon -Wa,--noexecstack -Wformat -Werror=format-security -std=c++11  -O3

Sorry @xiaozhuai, I'm not familiar with compilation on Android. I did notice that --export-dynamic is not present in your flags. Did you try that?

@fmela I use clang, there is no --export-dynamic supported : (

1   14_framebuffer                      0x00000001024de654 _Z11initProgramv + 52
2   14_framebuffer                      0x00000001024e47f6 main + 1206
3   libdyld.dylib                       0x00007fff6ce713d5 start + 1

I also try it on my mac. It seems abi::__cxa_demangle not working.

Apple LLVM version 10.0.1 (clang-1001.0.46.4)
Target: x86_64-apple-darwin18.7.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin

@xiaozhuai Sorry, I should have mentioned that that is a linker flag, not a compiler flag. You might need to try -Wl,--export-dynamic.

@fmela It works now, it should be -Wl,-export-dynamic. Thank you very much!

As this code work just... perfectly, can I add it to a library addon that have to make C++ development easier with a this library?

Would it be possible to add an open source license to this so other projects can more freely use it? If you don't know which you prefer, this is a really simple guide to help: https://choosealicense.com/

It doesn't work in Windows , you should state it only work in Linux

This solution is nice but it's lacking the source code file and line number... I found backward-cpp (https://github.com/bombela/backward-cpp) to be better fitting my needs.,

This solution is nice but it's lacking the source code file and line number... I found backward-cpp (https://github.com/bombela/backward-cpp) to be better fitting my needs.,

nice, thanks for updating the thread here!