[clang-tools-extra] [clang-tidy] performance-unnecessary-copy-init: Add a hook... (PR #73921)

[Clement Courbet via cfe-commits]

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@@ -261,21 +262,27 @@ void UnnecessaryCopyInitialization::registerMatchers(MatchFinder *Finder) {
                      this);
 }
 
+UnnecessaryCopyInitialization::CheckContext::CheckContext(
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legrosbuffle wrote:

Given that we are deriving `IssueFix`, `IsVarUnused`, `IsVarOnlyUsedAsConst` from `Var`, `BlockStmt`, ... it sounds natural to have a ctor there. Otherwise we risk creating a `CheckContext` in an invalid state.

https://github.com/llvm/llvm-project/pull/73921