[clang] [clang] Track source deduction guide for alias template deduction guides (PR #123875)

[via cfe-commits]

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@@ -2290,18 +2290,21 @@ CXXDeductionGuideDecl *CXXDeductionGuideDecl::Create(
     ASTContext &C, DeclContext *DC, SourceLocation StartLoc,
     ExplicitSpecifier ES, const DeclarationNameInfo &NameInfo, QualType T,
     TypeSourceInfo *TInfo, SourceLocation EndLocation, CXXConstructorDecl *Ctor,
-    DeductionCandidate Kind, Expr *TrailingRequiresClause) {
-  return new (C, DC)
-      CXXDeductionGuideDecl(C, DC, StartLoc, ES, NameInfo, T, TInfo,
-                            EndLocation, Ctor, Kind, TrailingRequiresClause);
+    DeductionCandidate Kind, Expr *TrailingRequiresClause,
+    const CXXDeductionGuideDecl *GeneratedFrom,
+    SourceDeductionGuideKind SourceKind) {
+  return new (C, DC) CXXDeductionGuideDecl(
+      C, DC, StartLoc, ES, NameInfo, T, TInfo, EndLocation, Ctor, Kind,
+      TrailingRequiresClause, GeneratedFrom, SourceKind);
 }
 
 CXXDeductionGuideDecl *
 CXXDeductionGuideDecl::CreateDeserialized(ASTContext &C, GlobalDeclID ID) {
   return new (C, ID) CXXDeductionGuideDecl(
       C, nullptr, SourceLocation(), ExplicitSpecifier(), DeclarationNameInfo(),
       QualType(), nullptr, SourceLocation(), nullptr,
-      DeductionCandidate::Normal, nullptr);
+      DeductionCandidate::Normal, nullptr,
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cor3ntin wrote:

Can you add comments for all the nullptr arguments?

https://github.com/llvm/llvm-project/pull/123875