[PATCH] D149206: [clang][driver] Enable MisExpect diagnostics flag outside of CC1

Wed Apr 26 11:04:24 PDT 2023

paulkirth added inline comments.

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Comment at: clang/test/Driver/clang_f_opts.c:144
+// RUN: %clang -### -S -fprofile-instr-use=%t.profdata -fdiagnostics-misexpect-tolerance=10 -Wmisexpect %s 2>&1 | FileCheck %s --check-prefix=CHECK-MISEXPECT-TOLLERANCE
+// CHECK-MISEXPECT-TOLLERANCE-NOT: argument unused {{.*}}-fdiagnostics-misexpect-tolerance=
+
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hans wrote:
> Instead of checking for absence of the warning, could we just check that the flag is present among the cc1 flags? I think that's how most of the other tests here do it.
It took me a minute to realize what you meant here. I was pretty surprised to find out that `"-fdiagnostics-misexpect-tolerance=10"` is how we test for `cc1`, but `'-fdiagnostics-misexpect-tolerance='` is a test for an error/warning string. The reason I wrote the check this way was so that I wouldn't accidentally match on the non-warning case.

TBH Ithink checking the `cc1` flags like this is pretty brittle. They would all silently pass (even when they shouldn't) if the warning diagnostic used `"` instead of `'`. I'm sure some other tests would fail/need to be changed in that case, but there wouldn't be any indication that these tests wouldn't be functioning as intended.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D149206/new/

https://reviews.llvm.org/D149206