[clang] [FrontEnd] Use SetVector (NFC) (PR #107743)

[Kazu Hirata via cfe-commits]

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@@ -4082,8 +4080,10 @@ std::string RewriteModernObjC::SynthesizeBlockFunc(BlockExpr *CE, int i,
 
   // Create local declarations to avoid rewriting all closure decl ref exprs.
   // First, emit a declaration for all "by ref" decls.
-  for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
-       E = BlockByRefDecls.end(); I != E; ++I) {
+  for (llvm::SmallSetVector<ValueDecl *, 8>::iterator
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kazutakahirata wrote:

Fixed in the latest iteration.  Thanks!

https://github.com/llvm/llvm-project/pull/107743