How do I do source level debug of library

Question

I have a following setup. Although my working setup deals with ARM compiler Real View Developer Suite (RVDS) 3.2 on a Windows host, the situation could be generic for any other C compiler on any host.

I build a ARM library (static library - .a file) of C code using RVDS 3.2 compiler toolchain on Windows host. Then I link this library with an application using an ARM-Linux compiler toolchain on a Linux host, to get a ARM executable. Now when I try to debug this generated ARM executable on Linux using gdb, by trying to put a breakpoint in some function which is present in the library that is linked, gdb is not able to put breakpoint there citing source not found. So I manually copied all the source files(*.c) used to create the library in the Linux folder where the executable file is present. Still gdb fails to put a breakpoint. So now I started thinking:

1. How can I do source level debugging of this library which I create on Windows using a different compiler chain by launching the executable which is generated by linking this library to an application, in gdb. Is it possible? How can I do it? Is there any compiler option in RVDS compiler toolchain to enable this library source level debug?

2. Do I need to copy the source files to linux in exactly same folder structure as that is present in windows for those source files?

Answer 1

You could try to see if mimicking the exact same directory structure works. If you're not sure what directory structure the compiler annotated in the debug info in the executable, you can always look at it with dwarfdump (on linux).

Answer 2

First, GDB does not need any source to put breakpoints on functions; so your description of what is actually happening is probably inaccurate. I would start by verifying that the function you want to break on is actually there in the binary:

  nm /path/to/app | grep function_desired

Second, to do source level debugging, GDB needs debug info in a format GDB understands. On Linux this generally means DWARF or STABS. It is quite possible that your RVDS compiler does not emit such debug info; if so, source level debugging will not be possible.

Answer 3

Did you build the library with debugging enabled (-g option)? Without that, there would be difficulties identifying lines etc.