[clang] [diagtool] Make the BuiltinDiagnosticsByID table sorted (PR #120321)

[Karl-Johan Karlsson via cfe-commits]

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@@ -23,28 +23,29 @@ llvm::ArrayRef<DiagnosticRecord> diagtool::getBuiltinDiagnosticsByName() {
   return llvm::ArrayRef(BuiltinDiagnosticsByName);
 }
 
-
 // FIXME: Is it worth having two tables, especially when this one can get
 // out of sync easily?
+// clang-format off
 static const DiagnosticRecord BuiltinDiagnosticsByID[] = {
 #define DIAG(ENUM, CLASS, DEFAULT_MAPPING, DESC, GROUP, SFINAE, NOWERROR,      \
              SHOWINSYSHEADER, SHOWINSYSMACRO, DEFER, CATEGORY)                 \
   {#ENUM, diag::ENUM, STR_SIZE(#ENUM, uint8_t)},
 #include "clang/Basic/DiagnosticCommonKinds.inc"
-#include "clang/Basic/DiagnosticCrossTUKinds.inc"
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
 #include "clang/Basic/DiagnosticSerializationKinds.inc"
 #include "clang/Basic/DiagnosticLexKinds.inc"
 #include "clang/Basic/DiagnosticParseKinds.inc"
 #include "clang/Basic/DiagnosticASTKinds.inc"
 #include "clang/Basic/DiagnosticCommentKinds.inc"
+#include "clang/Basic/DiagnosticCrossTUKinds.inc"
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karka228 wrote:

> This seems brittle - Maybe we should call `std::sort` somewhere instead?

I agree that it is a bit brittle, but it is hard to find a good place where to insert a `std::sort`. As @kadircet  wrote it is probably better in the future to solve this in a better way in tablegen.

https://github.com/llvm/llvm-project/pull/120321