[clang] [APINotes] Match function-like Where.Parameters in Sema (PR #205307)

[Gábor Horváth via cfe-commits]

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@@ -0,0 +1,55 @@
+#ifndef WHERE_PARAMETERS_SEMA_H
+#define WHERE_PARAMETERS_SEMA_H
+
+using AliasInt = int;
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Xazax-hun wrote:

I think it would be nice to have a test with multiple layers of aliasing (I think it is fine if we only match the outermost and the fully desugared but not the intermediate ones). 

I also wonder if we want to set up a separate kind of tests to extract the string that we want to match against from a declaration. I am thinking of a unit test where we can easily pass in a string that describes a declaration and the expected extracted string. That being said such a testing infrastructure can be a follow-up, does not need to be part of this PR (and I am also fine not doing it if it is too much work). 

https://github.com/llvm/llvm-project/pull/205307