bad or irreducible absolute expression

Bughunter · **Posted:** Sat Jun 02, 2007 11:52 am

When compiling my Multiboot header stub, I get this error:

Code:

Error: bad or irreducible absolute expression

It complains about this line:

Code:

.comm stack, STACK_SIZE, 32               # reserve 16K stack on a quadword boundary

I defined STACK_SIZE (in an external header file, but it doesn't matter if I define it in the same file) with:

Code:

#define STACK_SIZE 0x4000

Can anyone tell me what could be wrong? I have included my Multiboot stub source codes if anyone wants to have a look.

Thanks

nick8325 · **Joined:** Wed Oct 18, 2006 5:49 am **Posts:** 200

It works here...do you run multiboot_header.S through the preprocessor first? The assembler doesn't know about #defines. gcc will preprocess the file itself, if you run "gcc" instead of "as".

Bughunter · **Posted:** Sun Jun 03, 2007 3:36 am

Hmm that could be it, so I should just call GCC instead of AS?

EDIT: Omg of course... It now works! Thank you!

Oh btw if anyone uses the code I posted above, make sure you correct the Multiboot header checksum (it's invalid) to:

Code:

.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)

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