[clang] [clang] Implement CWG1878 "`operator auto` template" (PR #78103)

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github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


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``````````bash
git-clang-format --diff fb2cc9b9fc5ae5a544e3009ae153f5ae83c5a89c 522c7dff31a6f63995877674f9f4282ae60f7aaa -- clang/lib/Sema/SemaDeclCXX.cpp clang/test/CXX/drs/dr18xx.cpp clang/test/SemaCXX/deduced-return-type-cxx14.cpp
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View the diff from clang-format here.
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``````````diff
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 613dccbf44..0e7a43859c 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -11322,13 +11322,18 @@ Decl *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) {
       << ClassType << ConvType;
   }
 
-  if (FunctionTemplateDecl *ConversionTemplate
-                                = Conversion->getDescribedFunctionTemplate()) {
+  if (FunctionTemplateDecl *ConversionTemplate =
+          Conversion->getDescribedFunctionTemplate()) {
     if (ConvType->isUndeducedAutoType()) {
       Diag(Conversion->getTypeSpecStartLoc(), diag::err_auto_not_allowed)
-        << Conversion->getTypeSourceInfo()->getTypeLoc().getContainedAutoTypeLoc().getSourceRange()
-        << llvm::to_underlying(Conversion->getConversionType()->getAs<AutoType>()->getKeyword())
-        << /* in declaration of conversion function template */ 24;
+          << Conversion->getTypeSourceInfo()
+                 ->getTypeLoc()
+                 .getContainedAutoTypeLoc()
+                 .getSourceRange()
+          << llvm::to_underlying(Conversion->getConversionType()
+                                     ->getAs<AutoType>()
+                                     ->getKeyword())
+          << /* in declaration of conversion function template */ 24;
     }
 
     return ConversionTemplate;

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https://github.com/llvm/llvm-project/pull/78103