[clang] [clang] CTAD alias: Emit a more descriptive diagnostic message when is_deducible constraint is evaluated to false. (PR #92389)

[Haojian Wu via cfe-commits]

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@@ -111,7 +111,7 @@ struct Foo {
 template <typename X, int Y>
 using Bar = Foo<X, sizeof(X)>; // expected-note {{candidate template ignored: couldn't infer template argument 'X'}} \
                                // expected-note {{candidate template ignored: constraints not satisfied [with X = int]}} \
-                               // expected-note {{because '__is_deducible}}
+                               // expected-note {{can not deduce template arguments for 'Bar' from the type 'Foo<int, 4UL>'}}
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hokein wrote:

ah, this was left when I adjusted the message. Done.

https://github.com/llvm/llvm-project/pull/92389