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GNU linker script question

Hi,

I'm working on an embedded project at home using GNU gcc & ld. I need to burn a function into a particular flash rom address. My attempt will be to place the function in its own file and define a section like:

SECTIONS { MySection 0x10000: { MyFile.o } _MySectionEnd = . ; }

Then, in my app, I should be able to refer to _MySectionEnd to get the end address of the function. I'm pretty sure this, or a variant will work (my syntax might not be 100% as I'm an ld newbie).

But, is there a better way? Also, while this is OK for one, or a few functions, it would be a pain if I ever had to do a lot of 'em. I know there's a "section" attribute for gnu C, so I was wondering if I can create one or more MySection1 and _MySection1End symbol pairs in a linker script and somehow place each function at the desired section while all functions reside in one file?

Thanks for the ideas!

Jim

Reply to
Jim
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Just to avoid a bunch of comments correcting me, the linker script above turned out to be more like:

.text : { MyFunc.o (.text) _MyFuncEnd = .; *(.text) *(.rodata) . = ALIGN(0x4) ; __etext = .; } > ram

Jim

p.s. I did finally find something about causing gcc to create each function in it's own section as if it were in its own file, but it didn't say how you knew what the section names would be. I'm guessing it would be a derivative of the function name.

Reply to
Jim

Yes, go to and download the crtls package for an example of how it can be done.

-a

Reply to
ammonton

If you are only looking for the end address of a single function, then you could put that function in its own named section (look in the gcc manual for "function attributes"). I've done this on several targets for putting flash routines in a separate section so that they run from ram rather than flash.

Reply to
David Brown

That's an interesting site. Thanks.

Jim

Reply to
Jim

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