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Re: basic asm and memory clobbers
- From: <Paul_Koning at Dell dot com>
- To: <iant at google dot com>
- Cc: <dw at limegreensocks dot com>, <gcc at gcc dot gnu dot org>
- Date: Tue, 24 Nov 2015 17:59:49 +0000
- Subject: Re: basic asm and memory clobbers
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> On Nov 24, 2015, at 12:49 PM, Ian Lance Taylor <iant@google.com> wrote:
>
> On Tue, Nov 24, 2015 at 8:58 AM, <Paul_Koning@dell.com> wrote:
>>
>> I'm really concerned with loosening the meaning of basic asm. I
>> wish I could find the documentation that says, or implies, that it
>> is a memory clobber. And/or that it is implicitly volatile.
>
> The volatile one is right there in the current docs.
>
> https://gcc.gnu.org/onlinedocs/gcc/Basic-Asm.html#Basic-Asm
>
> "All basic asm blocks are implicitly volatile."
Ok, that's what I remembered. I reported finding that this was not implemented correctly, some number of versions ago.
paul