How to place a variable at a given absolute address in memory (with GCC)

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I don’t know, but you can easily create a workaround like this:

int *var = (int*)0x40001000;
*var = 4;

It’s not exactly the same thing, but in most situations a perfect substitute. It will work with any compiler, not just GCC.

If you use GCC, I assume you also use GNU ld (although it is not a certainty, of course) and ld has support for placing variables wherever you want them.

I imagine letting the linker do that job is pretty common.

Inspired by answer by @rib, I’ll add that if the absolute address is for some control register, I’d add volatile to the pointer definition. If it is just RAM, it doesn’t matter.

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