[PATCH] D24799: [XRay] Check in Clang whether XRay supports the target when -fxray-instrument is passed

[Dean Michael Berris via cfe-commits]

dberris added a comment.

In https://reviews.llvm.org/D24799#549634, @rSerge wrote:

> In https://reviews.llvm.org/D24799#549442, @dberris wrote:
>
> > What does the error actually look like? Can you add a test for it? It's unclear to me how this would read... for example does it say "XRay for arm is unsupported"?
>
>
> In the attached picture you can see how the error looks when cross-compiling with Clang from x86_64-Windows host to Thumb-Linux target. 
>  F2439489: Unsupported XRay target error.jpg <https://reviews.llvm.org/F2439489>
>  It says
>
> > clang++.exe: error: the clang compiler does not support 'XRay for armv6kz--linux-gnueabihf'
>


Thanks -- I that's really helpful.

A clearer message I think might read something like:

> the clang compiler does not support '-fxray-instrument' on '-mtriple=armv6kz-linux-gnueabihf'


Even if you drop the '-mtriple=' prefix, I think that might work better than "XRay for".

> I'll try to add tests.


Thanks -- an XFAIL for a platform you know it should fail for should be sufficient, without spelling out the actual error message in the test.


https://reviews.llvm.org/D24799