[Click] line numbers in click binary symbol table

[Ian Rose]

Hi list,

This may or may not be specific to Click, so apologies in advance if I 
am off topic.  I am attempting to do some debugging of my (userlevel) 
click app and I am finding that the symbol table of the resulting click 
binary has very few line numbers in it (as viewed by 'nm -l -C 
bin/click').  This is a problem for me because it means that basically 
every address that I pass to addr2line returns '??:0' for the file and 
line number.  I've also had some problems getting useful information out 
of coredumps (which is why I am messing about with addr2line instead of 
just gdb), perhaps for the same reason?

My knowledge is rather limited as far as compiling and linking go, so my 
question is whether this is somehow Click's doing (perhaps its stripping 
most of the line numbers?) or whether this is normal gcc/ld behavior 
that I'm just unfamiliar with.  Other than click, I pretty much 
exclusively use C over C++ so if there is some different behavior for 
C++ code I wouldn't know it.  I've tried digging through the click 
Makefiles but I haven't found anything incriminating.  Also, I've 
confirmed that I am compiling with -g and I have tried both with and 
without -O2 with no noticeable difference.

Many thanks for any tips!
- Ian