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Re: basic asm and memory clobbers


>> To be clear, wouldn't asm("":) have the same effect?
>
> That does not matter.  It'd require source-code changes to
> users' code.

My suggestion was to allow the exception to the "basic asm in a function" warning, but change the docs to show using the new syntax. This does not require any user code change. But it kinda does matter whether or not it will work.

Copy/pasting my suggestion:

1) Change the docs to say asm("":), so future coders will do "the right thing."
2) Allow the exception for v6.
3) Re-evaluate if-and-when we continue with the deprecation process.

It may not be clear from this, but I don't expect step 3 to happen until at least v7.

And saying "the right thing" may be a bit flip. But if deprecating basic asm is the path we are choosing, then telling users to use this syntax is how the text should read. Assuming it works.

> BTW, does that syntax work for really olden gcc
> (say 2.95 era)?

The oldest docs I can find are 2.95.3, and they talk about the extended asm syntax, so I assume so: https://gcc.gnu.org/onlinedocs/gcc-2.95.3/gcc_4.html#SEC93

> Either way, we promised 'asm("")'.  I'm pretty
> sure the empty string is identifiable.

It is.  I've already updated my code to support this exception.

dw


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