[clang] [Clang] Fix handling of brace ellison when building deduction guides (PR #94889)

[Haojian Wu via cfe-commits]

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@@ -335,3 +335,73 @@ namespace TTP {
 // CHECK-NEXT:      `-TemplateArgument type 'T':'type-parameter-0-0'{{$}}
 // CHECK-NEXT:        `-TemplateTypeParmType {{.+}} 'T' dependent depth 0 index 0{{$}}
 // CHECK-NEXT:          `-TemplateTypeParm {{.+}} 'T'{{$}}
+
+namespace GH64625 {
+
+template <class T> struct X {
+  T t[2];
+};
+
+X x = {{1, 2}}, y = {1, 2};
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hokein wrote:

nit: `y = {1, 2}` is already working today. Let's just add the problematic test cases.

https://github.com/llvm/llvm-project/pull/94889