[libcxx-commits] [clang] [libcxx] [Clang] Normalize constraints before checking for satisfaction (PR #141776)

[Matheus Izvekov via libcxx-commits]

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@@ -9,20 +9,24 @@ concept C2 = C1<Y{}, V>;
 // sizeof(U) >= 4 [U = V (decltype(Y{}))]
 
 template<char W>
-constexpr int foo() requires C2<int, W> { return 1; }
+constexpr int foo() requires C2<int, W> { return 1; } // #cand1
 // sizeof(U) >= 4 [U = W (decltype(int{}))]
 
 template<char X>
 // expected-note at +1{{candidate function}}
-constexpr int foo() requires C1<1, X> && true { return 2; }
+constexpr int foo() requires C1<1, X> && true { return 2; } // #cand2
 // sizeof(U) >= 4 [U = X (decltype(1))]
 
 static_assert(foo<'a'>() == 2);
+// expected-error at -1 {{call to 'foo' is ambiguous}}
+// expected-note@#cand1 {{candidate function}}
+// expected-note@#cand2 {{candidate function}}
 
 template<char Z>
-// expected-note at +1{{candidate function}}
-constexpr int foo() requires C2<long long, Z> && true { return 3; }
+constexpr int foo() requires C2<long long, Z> && true { return 3; } // #cand3
 // sizeof(U) >= 4 [U = Z (decltype(long long{}))]
 
 static_assert(foo<'a'>() == 3);
-// expected-error at -1{{call to 'foo' is ambiguous}}
\ No newline at end of file
+// expected-error at -1{{call to 'foo' is ambiguous}}
+// expected-note@#cand1 {{candidate function}}
+// expected-note@#cand3 {{candidate function}}
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mizvekov wrote:

What is the rationale for these test changes?

https://github.com/llvm/llvm-project/pull/141776