[clang] [llvm] [clang] Add `-verify-directives` cc1 flag (PR #179835)

[Erich Keane via cfe-commits]

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@@ -3451,22 +3451,40 @@ are similar.
 Testing
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 All functional changes to Clang should come with test coverage demonstrating
-the change in behavior.
+the change in behavior. There are four kinds of such tests.
+
+The first kind is unit tests. Such tests are placed in ``clang/test/unittest``.
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erichkeane wrote:

Rather than 'The first kind is...' etc, just make this a bullet list with:

`Unit Tests: Such...`

You'll have to come up with titles for each, but it will make them more readable.

https://github.com/llvm/llvm-project/pull/179835