[clang] [clang] Redeclare function templates instances per primary template (PR #110387)

[Matheus Izvekov via cfe-commits]

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@@ -0,0 +1,84 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++26 %s
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mizvekov wrote:

Yeah I think this is big enough to be on its own file.

https://github.com/llvm/llvm-project/pull/110387