[PATCH] ARM: omap1: fix building with clang IAS

Tony Lindgren tony at atomide.com
Tue Mar 9 09:57:37 GMT 2021


* Arnd Bergmann <arnd at kernel.org> [210308 15:35]:
> From: Arnd Bergmann <arnd at arndb.de>
> 
> The clang integrated assembler fails to build one file with
> a complex asm instruction:
> 
> arch/arm/mach-omap1/ams-delta-fiq-handler.S:249:2: error: invalid instruction, any one of the following would fix this:
>  mov r10, #(1 << (((NR_IRQS_LEGACY + 12) - NR_IRQS_LEGACY) % 32)) @ set deferred_fiq bit
>  ^
> arch/arm/mach-omap1/ams-delta-fiq-handler.S:249:2: note: instruction requires: armv6t2
>  mov r10, #(1 << (((NR_IRQS_LEGACY + 12) - NR_IRQS_LEGACY) % 32)) @ set deferred_fiq bit
>  ^
> arch/arm/mach-omap1/ams-delta-fiq-handler.S:249:2: note: instruction requires: thumb2
>  mov r10, #(1 << (((NR_IRQS_LEGACY + 12) - NR_IRQS_LEGACY) % 32)) @ set deferred_fiq bit
>  ^
> 
> The problem is that 'NR_IRQS_LEGACY' is not defined here. Apparently
> gas does not care because we first add and then subtract this number,
> leading to the immediate value to be the same regardless of the
> specific definition of NR_IRQS_LEGACY.
> 
> Neither the way that 'gas' just silently builds this file, nor the
> way that clang IAS makes nonsensical suggestions for how to fix it
> is great. Fortunately there is an easy fix, which is to #include
> the header that contains the definition.

Acked-by: Tony Lindgren <tony at atomide.com>



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