[PATCH] D54769: [FileCheck] New option -warn

[Paul Robinson via Phabricator via llvm-commits]

probinson added a comment.

In D54769#1308894 <https://reviews.llvm.org/D54769#1308894>, @SjoerdMeijer wrote:

> > So, I'm not convinced that we can have a diagnostic for your case 3 that would really be meaningful and useful.
>
> That is really unfortunate and problematic. Apologies, but just for completeness, this was that example:
>
>   RUN: llc -mtriple=arm-linux-gnueabi %s -o - | FileCheck %s -check-prefix=FOO
>   define void @FOO() {
>   entry:
>     ; FOO-LABEL: FOO:
>     ; DOO:             mov  pc, lr
>     ret void
>   }
>   
>
> It's really not difficult to make this mistake, and I really would like to solve this one too. My previous approach might be wrong, so I am going to look again if I can get it to reliably error in this case.


And if the input was this:

  RUN: llc -mtriple=arm-linux-gnueabi %s -o - | FileCheck %s -check-prefix=FOO
  define void @FOO() {
  entry:
    ; FOO-LABEL: FOO:
    ; DOO:             mov  pc, lr
    ; FOO:             ret void
  }

there is no reasonable way to flag the DOO line as a mistake.  In fact, typos in the prefix are a tactic I've often used to "comment out" directives, for one reason or another, and I would not want that tactic to start triggering warnings.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54769/new/

https://reviews.llvm.org/D54769