Question about _SFR_IO_ADDR() macro

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atomicdog
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Posted by atomicdog: Fri. Feb 8, 2008 - 07:31 AM
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This macro is defined in sfr_defs.h like...

#define _SFR_IO_ADDR(sfr) ((sfr) - __SFR_OFFSET)

But when I create a preprocessed source file it expands like...
app.c

_SFR_IO_ADDR(0x3F);

app.i

(((uint16_t) &(0x3F)) - 0x20);

How and/or why is the addressing symbol '&' there?

~~John
TWI C source code

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Tools, Compilers and General Programming
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atomicdog
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Posted by atomicdog: Fri. Feb 8, 2008 - 08:00 AM
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I was reading the file wrong. the define I was looking at was under the defined '_SFR_ASM_COMPAT' section.

~~John
TWI C source code

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