[LLVMdev] .align 0

[Sid Manning]

".align 0" triggers the following error:

a.s:2:8: error: alignment must be a power of 2
.align 0
        ^
In this case would it be reasonable to query the target for a default
or minimum value?  Only targets not implementing this would error out.

Thanks,

On 10/28/2013 03:00 PM, Jim Grosbach wrote:
> Apple’s assembler does use power-of-two for .align. I believe binutils
> does as well. I suspect the header file comment is in error and what’s
> actually happening is that the section in question has a minimum
> alignment on the system(s) in question, and so it just looks like it’s
> redundant. That is, I doubt we need to do anything here.
>
> -Jim
>
> On Oct 28, 2013, at 11:54 AM, Renato Golin <renato.golin at linaro.org
> <mailto:renato.golin at linaro.org>> wrote:
>
>> Hi Sid,
>>
>> It seems Apple's assembler used to treat .align 0 differently:
>>
>> https://developer.apple.com/library/mac/documentation/developertools/Reference/Assembler/040-Assembler_Directives/asm_directives.html
>>
>> If this is still the case, than we should have an option for what to
>> do in this case, maybe defaulting based on the triple?
>>
>> cheers,
>> --renato
>>
>>
>> On 28 October 2013 17:53, Sid Manning <sidneym at codeaurora.org
>> <mailto:sidneym at codeaurora.org>> wrote:
>>
>>
>>     I have several assembly files in a testsuite that use, ".align 0".
>>     I found a reference to, ".align 0" in ARM's elf.h that says .align
>>     0 is redundant and gas treats this as align 2.
>>
>>     Should the llvm-mc follow this convention?
>>
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