On 11/10/2016 08:24 AM, Martin Liška wrote:
On 11/10/2016 05:17 PM, David Edelsohn wrote:
Maybe instead of adding "maybe", we need to change the severity of the
warning so that the warning is not emitted by default.
Adding the warning option to -Wextra can be solution. Is it acceptable
approach?
I don't think that's good. Now I understand the -pthreads thing, we
have different use cases.
1) user explicitly said -fprofile-update=FOO. They shouldn't have to
enable something else to get a diagnostic that FOO doesn't work.
2) driver implicitly said -fprofile-update=FOO, because the user said
-pthreads but the driver doesn't know if FOO is acceptable. We want to
silently fallback to the old behaviour.
The proposed solution addresses #2 by having the driver say
-fprofile-update=META-FOO. My dislike is that we're exposing this to
the user and they're going to start using it. That strikes me as
undesirable.
How hard is it to implement the fprofile-update option value as a list.
I.e. '-fprofile-update=atomic,single', with semantics of 'pick the first
one you can do'? If that's straightforwards, then that seems to me as a
better solution for #2. [flyby-thought, have 'atomic,single' as an
acceptable single option value?]
Failing that, Martin's solution is probably the sanest available
solution, but I'd like to rename 'maybe-atomic' to the more meaningful
'prefer-atomic'. With 'maybe-atomic', I'm left wondering if it looks at
the phase of the moon.
nathan
--
Nathan Sidwell
