[clang] [Sema] Fix parameter index checks on explicit object member functions (PR #165586)

[via cfe-commits]

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@@ -1,11 +1,16 @@
-// RUN: %clang_cc1 %s -verify -fsyntax-only
+// RUN: %clang_cc1 %s -std=c++23 -verify -fsyntax-only
 
 // expected-no-diagnostics
 
 class C_in_class {
 #include "../Sema/attr-callback.c"
 };
 
+class ExplicitParameterObject {
+  __attribute__((callback(2, 1))) void explicit_this_idx(this ExplicitParameterObject* self, void (*callback)(ExplicitParameterObject*));
+  __attribute__((callback(2, self))) void explicit_this_identifier(this ExplicitParameterObject* self, void (*callback)(ExplicitParameterObject*));
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Sirraide wrote:

Can you add some codegen tests as well to make sure that we actually generate the right callback metadata for explicit object parameters?

https://github.com/llvm/llvm-project/pull/165586