_mainCRTStartup/ctr0.S and thumb

Torsten@Robitzki.de Torsten@Robitzki.de
Mon Aug 4 11:25:00 GMT 2014

Hello Richard,

Am 04.08.2014 um 11:10 schrieb Richard Earnshaw <rearnsha@arm.com>:

> Cortex-m0 can only execute thumb code.  It doesn't support the A32 (ARM)
> instruction set.

yes, and that's why this version fails to work on a cortex-m0. Why are there arm32 instructions in thumb/crt0.o? Is it possible to use the newlib with a cortex-m0 cpu and if, how would I have to configure it? 

I've poked a little bit into other functions of the newlib and all, but _mainCRTStartup/_start seem to be correctly compiled to thumb instructions. So I can make use of the newlib except for functions that needs some initialization. Is there a subset of the C library functions that are known to be used without initialization?

Thank you,


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