[clang] [Clang] Implement P2308R1 - Template Parameter Initialization. (PR #73103)

[Tom Honermann via cfe-commits]

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@@ -61,6 +61,14 @@ namespace dr2026 { // dr2026: 11
   }
 }
 
+namespace dr2049 { // dr2049: 18 drafting
+#if __cplusplus > 202002L
+template <int* x = {}> struct X {};
+X<> a;
+X<nullptr> b;
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tahonermann wrote:

Perhaps add a same-type static assertion for `a` and `b` to ensure a consistent specialization is selected?

https://github.com/llvm/llvm-project/pull/73103