You can run gdb with –args parameter: gdb –args executablename arg1 arg2 arg3 If you are doing this often (e.g. when running GDB from a script), you might want to consider the following arguments to automate things further. First, you can place your GDB commands (such as ‘run’) in a text file and provide the … Read more
To resume execution at a new address, use jump (short form: j): jump LINENUM jump *ADDRESS The GDB manual suggests using tbreak (temporary breakpoint) before jumping. The linenum can be any linespec expression, like +1 for the next line. See @gospes’s answer on a related question for a handy skip macro that does exactly that. … Read more
Yes, here is how to make this work: // sample.h struct sample { int i; struct sample *less; struct sample *more; }; // main.c #include <stdio.h> #include <assert.h> #include “sample.h” int main() { struct sample sm; sm.i = 42; sm.less = sm.more = &sm; printf(“&sm = %p\n”, &sm); assert(sm.i == 0); // will fail } … Read more
The following worked for me. Not sure whether there is a better way. Install libc6-dbg (which you have already done): sudo apt-get install libc6-dbg Install the eglibc-source package (ubuntu actually uses eglibc): sudo apt-get install eglibc-source. Unpack the tar file that was installed in /usr/src/glibc: /usr/src/glibc $ sudo tar xvf eglibc-2.19.tar.xz Crank up gdb and … Read more
Well, this wasn’t easy – but I think I somewhat got it 🙂 I went through a bunch of failed attempts (posted here); relevant code is below. Basically, the problem in a “next/step until breakpoint” is how to determine whether you’re “on” a breakpoint or not, if the debugger is stopped (at a step). Note … Read more
-g tells the compiler to store symbol table information in the executable. Among other things, this includes: symbol names type info for symbols files and line numbers where the symbols came from Debuggers use this information to output meaningful names for symbols and to associate instructions with particular lines in the source. For some compilers, … Read more
Basically, in this example I wanted to get some variable values in particular places of the code; and have them output until the program crashes. So here is first a little program which is guaranteed to crash in a few steps, test.c: #include <stdio.h> #include <stdlib.h> int icount = 1; // default value main(int argc, … Read more
This is caused by latest gdb 8.1, downgrade gdb to 8.0.1 could solve this problem. How to downgrade to gdb 8.0.1 Unlink current gdb: brew unlink gdb Install gdb 8.0.1: brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/9ec9fb27a33698fc7636afce5c1c16787e9ce3f3/Formula/gdb.rb Optional: avoid upgrade gdb with brew pin gdb
If you’re running on Linux, use objdump –debugging. There should be an entry for each object file in the library. For object files without debugging symbols, you’ll see something like: objdump –debugging libvoidincr.a In archive libvoidincr.a: voidincr.o: file format elf64-x86-64 If there are debugging symbols, the output will be much more verbose.