Strange warning in ddd

[Tiago Silva]

Binary package hint: ddd

Greetings.

Everytime I pass an executable to ddd I get a weird message dialogue:
Title - DDD: No Source
Content - /home/sysdeps/i386/elf/start.S: No such file or directory

This occurs in Jaunty.

Thanks!

[Tiago Silva (tiagosilva)]

This is also occurring in Karmic.

[Tiago Silva (tiagosilva)]

Also, after stepping the last source line, I get the following message dialogue:
Title - DDD: No Source
Content - /home/tiago/libc-start.c: No such file or directory
or
Content - /home/tiago/Ubuntu One/isc/a2/libc-start.c: No such file or directory

[Martin Gilchrist (gilchrist-martin)]

Hi.

I'm also seeing this error on 64 bit:

/sysdeps/x86_64/elf/start.S: No such file or directory.

Has this been confirmed as a bug?

Maybe we just haven't set some paths correctly.

Martin.

[Tiago Silva (tiagosilva)]

Added a gzipped copy of my ~/.ddd/log file in order to be more in conformance with a proper bug report.

[Paolo Cancedda (pac72)]

To me this does not seem a bug, but rather an expected behaviour of gdb.
The main issue is your executable not having debug symbols (in logs I see the messages 'No line number information available' and 'No symbol table is loaded. Use the "file" command.'). With gcc/as you need to compile/assemble providing the option "-g".
Secondarily, if I'm not mistaken, you have libc with debugging symbols but without sources (this is not a problem, it's uncommon to have libc sources installed, usually you have them only if you want to debug ). start.S and libc-start.c belong to libc and contain the code responsible for calling main() function of your program after a bit of initialization work.

[Paolo Cancedda (pac72)]

Addendum to previous comment: usually you have libc sources only if you are interested in debugging libc itself or if you want/need to understand how it works.

[Tiago Silva (tiagosilva)]

Thanks for your input, Paolo.

As far as I recall the binaries were assembled with either "-g" or "-ggdb".

How does one install these libc sources, Paolo? I will try to reproduce all the steps in my Maverick install.

Thanks again!

[Alberto Cuda (alberto-cuda)]

Looking at the log, it looks like a gdb issue. Please try this:

$ gdb /home/tiago/Documents/isc/a2/9
(gdb) list

If you get that warning, instead of something like:
1 .data
2 isc: .long 0x7d
3 tp: .long 0x20
4 .text
5 .globl main
6 main:
7 movl isc,%eax
8 movl %eax,%ebx
9 movl tp,%eax
10 nop
then for some reason gdb is defaulting to '_start' instead of 'main' when listing at startup.

Cheers.
Alberto.

[Tiago Silva (tiagosilva)]

Alberto, Paolo:
Using my Maverick install, now everything goes fine on gdb and ddd, with the exception that ddd starts throwing warnings after it reaching 'ret' via Step. This probably has to do with Paolo's second point (sources).