RE: [avr-gcc-list] dtostrf and the dreaded "relocation truncated to fit: R_AVR_13_PCREL" error

[Eric Weddington]

> -----Original Message-----
> From: 
> address@hidden 
> [mailto:address@hidden
> org] On Behalf Of rtwas
> Sent: Friday, April 06, 2007 12:10 AM
> To: address@hidden
> Subject: [avr-gcc-list] dtostrf and the dreaded "relocation 
> truncated to fit: R_AVR_13_PCREL" error
> 
> 
> 
>             gcc: avr-gcc (GCC) 4.1.1
>            libc: avr-libc-1.4.4
> atmega128:
> 
> Hello,
> 
> On a current project, as soon as I add
> 
> dtostrf(f0, 4, 4, str2);
> or
> dtostre((float) f0, str2, 4,0);
> 
> to one of my source files I get:
> 
> 
> /usr/local/atmel/bin/avr-gcc -g -Os -Wall -mcall-prologues 
> -mmcu=atmega128 -save-temps   main.o spim.o spim_tmr0.o diag.o uart.o 
> cmd.o cmd_spi.o -o avr_sdiag0.obj
> /usr/local/atmel/lib/gcc/avr/4.1.1/../../../../avr/lib/avr5/li
> bc.a(pow.o): 
> In function `pow':
> ../../../libm/fplib/pow.S:100: relocation truncated to fit: 
> R_AVR_13_PCREL against symbol `__mulsf3' defined in .text section in 
> 

Try adding -lm to your linker command line (above) to link in the math
library from avr-libc rather than relying on libgcc.