[avr-gcc-list] 'relocation truncated to fit' diagnosis ideas?

[Jim Brain]

Pardon my question if it's obvious, I've had quite a night casing 
compiler issues.

Received this error tonight after enabling a new chunk of code to 
compile on a MEGA168 target

I noticed some fixes in newer AVR GCC versions for things like this, so 
I pulled GCC 4.7.0:

http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=117504&postdays=0&postorder=asc

I got further, but after copying back in all the code I had pulled out, 
it still complains about R_AVR_13_PCREL errors.

-lm and relax have been on all the time.

Is there a tutorial that describes how to restructure your code or your 
Makefile to overcome this issue?  I understand it's a RJMP 13 bit 
address overrun issue during linking, but I am lost on how to address 
the issue.  Essentially the same code compiles fine for MEGA162, and the 
current codebase compiles fine if I leave off a few calls in main.c.

My code is GPL, available to anyone who is keen to see it fail themselves.

Jim