Every time you use the "expr" command, we compile a tiny c++ code snippet inject it into the target process and execute it. If you type "log enable lldb expr" you should be able to follow how exactly that works. You can use pretty much any c++ construct in the expression including declaring variables/types: (lldb) expr -- char s[]="qwerty"; for(int i=0; i < sizeof s; ++i) printf("%d: %c\n", i, s[i]); 0: q 1: w 2: e 3: r 4: t 5: y 6:
So, if your question is "do we support compiling code and running it in the debugged process", then the answer is yes. If you want something that would automatically intercept some function to execute your code while the process is running (some kind of dynamic instrumentation), then the answer is no. (But I don't see any mention of that on the gdb page you quoted either). cheers, pavel On 12 February 2017 at 18:34, Roman Popov via lldb-dev <lldb-dev@lists.llvm.org> wrote: > Hello Benjamin , all > >>>I recently started using lldb to write a basic instrumentation tool for >>>tracking the values of variables at various code-points in a program. > > I have the same problem of tracing some variables and debugging application > post-mortem. Without knowing about your experience I've started walking same > path and encountered same problem. In my case inserting an empty callback > slows-down application by 100x. This is not acceptable for me, because > instead of minutes I got hours of runtime. > > Did you found any faster solution? > > My current plan is to solve it with code injection: I plan to find pointers > to interesting values using debugger scripting and then inject code to trace > them. > > Does LLDB supports code injection ? I've found information only about gdb > https://sourceware.org/gdb/onlinedocs/gdb/Compiling-and-Injecting-Code.html > but not about lldb > > > -Roman > > > _______________________________________________ > lldb-dev mailing list > lldb-dev@lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev > _______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev