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m68k-coff: Unused memory region included in output file?


I've been using the following memory region setup for applications running on our custom M68K board:

MEMORY
{
 reserved (rwx) : ORIGIN = 0x000000, LENGTH = 4K
 ram (rwx) : ORIGIN = 0x001000, LENGTH = 1M-4K
 rom (rx) : ORIGIN = 0xF00000, LENGTH = 128K
 user (rx) : ORIGIN = 0xF20000, LENGTH = 768K
 registers (rx): ORIGIN = 0xFE0000, LENGTH = 16K
 sio (rx): ORIGIN = 0xFE4000, LENGTH = 16K
 ivhc (rx): ORIGIN = 0xFE8000, LENGTH = 16K
 vme (rx): ORIGIN = 0xFF0000, LENGTH = 64K
}

Of these I actually only use "ram", i.e. all sections have "> ram"; the rest are included mainly as a reminder of what the memory looks like. When building with gcc-2.95.3, it looks like only data from ram is included in the output file, but with 3.3.3 it's different - the "reserved" region seems to be written, too, even though no output data is directed to it. Or at least, the .text segment, which is written to the start of "ram" appears at offset 0x1000 of the actual program data within the file, while it used to start at the very beginning.

If I change "reserved (rwx)" to "reserved (rx)" this no longer happens. Actually that's the way it should have been set up from the beginning, and it may not even be such a great idea to include unused regions in the first place, but the point is that *something* has changed between gcc 2 and 3, and I'd like to know what.

Can anyone enlighten me?

- Toralf


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