[clang] [clang] ASTContext: flesh out implementation of getCommonNNS (PR #131964)

[Erich Keane via cfe-commits]

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@@ -13462,13 +13462,114 @@ static ElaboratedTypeKeyword getCommonTypeKeyword(const T *X, const T *Y) {
                                             : ElaboratedTypeKeyword::None;
 }
 
+static NestedNameSpecifier *getCommonNNS(ASTContext &Ctx,
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erichkeane wrote:

Would LOVE some sort of comments in this function.  it is really quite an adventure to review even now, but I can't imagine coming along this later.  A description and some sort of 'describe-the-flow' comments inline would be really helpful.

https://github.com/llvm/llvm-project/pull/131964