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Can't compile / compile MRC and MCR coprocessor instructions on iPhone?

It seems I can’t collect the MCR and MRC ARMv7 instructions (these are instructions for accessing the coprocessors) from the iPhone? I have some of these instructions in some built-in building blocks that work very well with the Code Sourcery gcc code design for another CortexA8 chip (OMAP chip), but Apple assemblers - the Clang assembler and their gnu assembler - throw errors:

{standard input}:41:bad instruction `MRC p15,0,r2,C9,C12,0' {standard input}:56:bad instruction `MCR p15,0,r0,C9,C12,0' {standard input}:78:bad instruction `MCR p15,0,r0,C9,C12,1' {standard input}:96:bad instruction `MCR p15,0,r0,C9,C12,2' {standard input}:119:bad instruction `MCR p15,0,r2,C9,C12,4' {standard input}:143:bad instruction `MCR p15,0,r0,C9,C12,5' {standard input}:165:bad instruction `MCR p15,0,r0,C9,C13,1' {standard input}:187:bad instruction `MCR p15,0,r0,C9,C13,2' {standard input}:209:bad instruction `MCR p15,0,r0,C9,C13,0' {standard input}:228:bad instruction `MRC p15,0,r0,C9,C13,0' {standard input}:253:bad instruction `MRC p15,0,r0,C9,C13,2'

Any ideas?

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(Originally as a comment on the question)

Random guess: did you try to change "MRC" to "mrc"? Apple has a relatively ancient ARM assembler that has problems with anything uppercase.

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