[clang] [clang-tools-extra] [llvm] [mlir] [clang][lldb][mlir] Fix some identical sub-expressions warnings (NFC) (PR #95715)

[Aaron Ballman via cfe-commits]

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@@ -4368,7 +4368,7 @@ bool Sema::DiagRedefinedPlaceholderFieldDecl(SourceLocation Loc,
   Diag(Loc, diag::err_using_placeholder_variable) << Name;
   for (DeclContextLookupResult::iterator It = Found; It != Result.end(); It++) {
     const NamedDecl *ND = *It;
-    if (ND->getDeclContext() != ND->getDeclContext())
+    if (ND->getDeclContext() != ClassDecl->getDeclContext())
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AaronBallman wrote:

This looks like a functional change to me; if no tests broke, we should probably figure out a test to add for this change.

https://github.com/llvm/llvm-project/pull/95715