A few libunwind examples:
- backtrace.cpp --- shows a demangled backtrace.
- more to come ...
On OSX, you should be able to just build as is. On other systems, you need to
link with -lunwind
. You also need cxxabi.h
, part of libstdc++.
I've used -O0
for the examples, because llvm is surprisingly good at doing
tail call elimination.
Shows how to print a backtrace.
You can double check that it works with gdb
or lldb
:
$ make backtrace
$ gdb ./backtrace
GNU gdb (GDB) 7.9.1
...
(gdb) break backtrace
Breakpoint 1 at 0x40086e: file backtrace.cpp, line 17.
(gdb) r
Starting program: .../backtrace
Breakpoint 1, backtrace () at backtrace.cpp:17
17 unw_getcontext(&context);
(gdb) bt
#0 backtrace () at backtrace.cpp:17
#1 0x0000000000400a02 in fac (n=0) at backtrace.cpp:51
#2 0x0000000000400a16 in fac (n=1) at backtrace.cpp:54
#3 0x0000000000400a16 in fac (n=2) at backtrace.cpp:54
#4 0x0000000000400a16 in fac (n=3) at backtrace.cpp:54
#5 0x0000000000400a16 in fac (n=4) at backtrace.cpp:54
#6 0x0000000000400a16 in fac (n=5) at backtrace.cpp:54
#7 0x0000000000400a16 in fac (n=6) at backtrace.cpp:54
#8 0x0000000000400a16 in fac (n=7) at backtrace.cpp:54
#9 0x0000000000400a16 in fac (n=8) at backtrace.cpp:54
#10 0x0000000000400a16 in fac (n=9) at backtrace.cpp:54
#11 0x0000000000400a16 in fac (n=10) at backtrace.cpp:54
#12 0x0000000000400a2a in main () at backtrace.cpp:60
(gdb) c
Continuing.
#1 0x0000000000400a02 sp=0x00007fffffffd7b0 fac(int) + 0x16
#2 0x0000000000400a16 sp=0x00007fffffffd7d0 fac(int) + 0x2a
#3 0x0000000000400a16 sp=0x00007fffffffd7f0 fac(int) + 0x2a
#4 0x0000000000400a16 sp=0x00007fffffffd810 fac(int) + 0x2a
#5 0x0000000000400a16 sp=0x00007fffffffd830 fac(int) + 0x2a
#6 0x0000000000400a16 sp=0x00007fffffffd850 fac(int) + 0x2a
#7 0x0000000000400a16 sp=0x00007fffffffd870 fac(int) + 0x2a
#8 0x0000000000400a16 sp=0x00007fffffffd890 fac(int) + 0x2a
#9 0x0000000000400a16 sp=0x00007fffffffd8b0 fac(int) + 0x2a
#10 0x0000000000400a16 sp=0x00007fffffffd8d0 fac(int) + 0x2a
#11 0x0000000000400a16 sp=0x00007fffffffd8f0 fac(int) + 0x2a
#12 0x0000000000400a2a sp=0x00007fffffffd910 main + 0xe
#13 0x0000003a7101ed5d sp=0x00007fffffffd920 __libc_start_main + 0xfd
#14 0x00000000004007a9 sp=0x00007fffffffd9e0 _start + 0x29
- "Deep Wizardry: Stack Unwinding", http://blog.reverberate.org/2013/05/deep-wizardry-stack-unwinding.html
Made by Christian Stigen Larsen in 2016
Put in the public domain.