On Fri, Apr 30, 2010 at 07:23:55AM -0700, Dave Hylands wrote: > On Fri, Apr 30, 2010 at 1:34 AM, Erik Christiansen wrote: > ...snip... > > > __vacant_flash = DEFINED (__eeprom_in_flash) ? __data_load_end + > > SIZEOF(.eeprom) : __data_load_end ; > > > > /* ld should't care whether it's one line or wrapped. */ > > > > > > Now there will by default be no wasted flash bytes, because > > __vacant_flash = __data_load_end , but when we use on the commandline: > > > > ld --defsym __eeprom_in_flash=1 # Or in gcc-friendly syntax: > > > > avr-gcc ... -D eeprom_in_flash > > Actually, I'm pretty sure this last one won't work. -D defines a > pre-processor symbol. I think you'd need to use something like > > avr-gcc ... -Wl,--defsym,__eeprom_in_flash=1
Yes, You're dead right. Precisely that feeds my first suggestion through gcc, and (unsurprisingly) works just as well as the direct invocation of ld. And Oh-oh, using gcc's "-D" isn't working for me either, in this context. Perhaps I have only used that syntax for #ifdef in individual compile units, after all. > > then our linker script will obediently shuffle __vacant_flash up to make > > room for .eeprom. > > > > Will that do? > > That looks to be generic enough to be useful. And (a little belatedly) it's confirmed to work, with the --defsym commandline syntax. Thanks for the expert critique. :-) Erik -- A computer is like an air conditioner, it works poorly when you open Windows. _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
