[clang] [clang] mangle placeholder for deduced type as a template-prefix (PR #106335)

[Aaron Ballman via cfe-commits]

================
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -std=c++20 %s -triple %itanium_abi_triple -emit-llvm -o - | FileCheck %s
+
+template <template <class> class S>
+void create_unique()
+  requires (S{0}, true) {}
+
+template <class Fn> struct A {
+  constexpr A(Fn) {};
+};
+
+template void create_unique<A>();
+// CHECK: @_Z13create_uniqueI1AEvvQcmtlT_Li0EELb1E(
----------------
AaronBallman wrote:

I think that's a reasonable path forward (presuming that we only need to revert one commit); that revert has to happen Real Soon™ though so we can get it backported.

https://github.com/llvm/llvm-project/pull/106335