[PATCH] D139305: [clang][driver] Support option '-mcpu' on target AVR.

[Ben Shi via Phabricator via cfe-commits]

benshi001 added a comment.

In D139305#3974946 <https://reviews.llvm.org/D139305#3974946>, @MaskRay wrote:

> This makes `-mmcu=` available for non-AVR targets, which is not right.
> Even for AVR, if this is a plain alias, is this really necessary? Usually having more than one aliases for one functionality just create confusion as users don't know which one is the canonical.
> I think one choice is for AVR users to migrate `-mmcu=` (if any) to `-mcpu=`, if there are a significant number of uses. Making a project buildable with Clang usually requires porting efforts, and this request may not be unreasonable.

I have changed to

1. Both '-mcpu' and '-mmcu' are supported for AVR, and '-mmcu' is not available to others;
2. '-mcpu' is superior to '-mmcu', and '-mcpu' is encouraged for newer clang built AVR projects;
3. A warning will emit if both are specified.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D139305/new/

https://reviews.llvm.org/D139305