Add 'enum_select' diagnostic selection to clang.

erichkeane · erichkeane · commit 4fbfdc801f6f · 2025-01-10T09:57:53.000-08:00
This causes us to generate an enum to go along with the select
diagnostic, which allows for clearer diagnostic error emit lines.

The syntax for this is:

%enum_select&lt;EnumerationName&gt;{%OptionalEnumeratorName{Text}|{Text2}}0

Where the curley brackets around the select-text are only required if an
Enumerator name is provided.

The TableGen here emits this as a normal 'select' to the frontend, which
permits us to reuse all of the existing 'select' infrastructure.
Documentation is the same as well.
diff --git a/clang/include/clang/Basic/CMakeLists.txt b/clang/include/clang/Basic/CMakeLists.txt
@@ -3,6 +3,11 @@ macro(clang_diag_gen component)
     -gen-clang-diags-defs -clang-component=${component}
     SOURCE Diagnostic.td
     TARGET ClangDiagnostic${component})
+
+  clang_tablegen(Diagnostic${component}Enums.inc
+    -gen-clang-diags-enums -clang-component=${component}
+    SOURCE Diagnostic.td
+    TARGET ClangDiagnostic${component}Enums)
 endmacro(clang_diag_gen)
 
 clang_diag_gen(Analysis)
diff --git a/clang/include/clang/Basic/DiagnosticAST.h b/clang/include/clang/Basic/DiagnosticAST.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_AST_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticASTEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticAnalysis.h b/clang/include/clang/Basic/DiagnosticAnalysis.h
@@ -22,6 +22,18 @@ enum {
 #undef DIAG
   NUM_BUILTIN_ANALYSIS_DIAGNOSTICS
 };
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticAnalysisEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticComment.h b/clang/include/clang/Basic/DiagnosticComment.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_COMMENT_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticCommentEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticCrossTU.h b/clang/include/clang/Basic/DiagnosticCrossTU.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_CROSSTU_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticCrossTUEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticDriver.h b/clang/include/clang/Basic/DiagnosticDriver.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_DRIVER_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticDriverEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticFrontend.h b/clang/include/clang/Basic/DiagnosticFrontend.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_FRONTEND_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticFrontendEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticInstallAPI.h b/clang/include/clang/Basic/DiagnosticInstallAPI.h
@@ -21,6 +21,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_INSTALLAPI_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticInstallAPIEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // namespace diag
 } // namespace clang
 #endif // LLVM_CLANG_BASIC_DIAGNOSTICINSTALLAPI_H
diff --git a/clang/include/clang/Basic/DiagnosticLex.h b/clang/include/clang/Basic/DiagnosticLex.h
@@ -22,6 +22,18 @@ enum {
 #undef DIAG
   NUM_BUILTIN_LEX_DIAGNOSTICS
 };
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticLexEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticParse.h b/clang/include/clang/Basic/DiagnosticParse.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_PARSE_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticParseEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticRefactoring.h b/clang/include/clang/Basic/DiagnosticRefactoring.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_REFACTORING_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticRefactoringEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticSema.h b/clang/include/clang/Basic/DiagnosticSema.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_SEMA_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticSemaEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -617,9 +617,11 @@ def err_ambiguous_inherited_constructor : Error<
   "constructor of %0 inherited from multiple base class subobjects">;
 def note_ambiguous_inherited_constructor_using : Note<
   "inherited from base class %0 here">;
-def note_using_decl_class_member_workaround : Note<
-  "use %select{an alias declaration|a typedef declaration|a reference|"
-  "a const variable|a constexpr variable}0 instead">;
+def note_using_decl_class_member_workaround
+    : Note<"use %enum_select<MemClassWorkaround>{%AliasDecl{an alias "
+           "declaration}|%TypedefDecl{a typedef declaration}|%ReferenceDecl{a "
+           "reference}|%ConstVar{a const variable}|%ConstexprVar{a constexpr "
+           "variable}}0 instead">;
 def err_using_decl_can_not_refer_to_namespace : Error<
   "using declaration cannot refer to a namespace">;
 def note_namespace_using_decl : Note<
diff --git a/clang/include/clang/Basic/DiagnosticSerialization.h b/clang/include/clang/Basic/DiagnosticSerialization.h
@@ -22,6 +22,19 @@ enum {
 #undef DIAG
   NUM_BUILTIN_SERIALIZATION_DIAGNOSTICS
 };
+
+#define DIAG_ENUM(ENUM_NAME)                                                   \
+  namespace ENUM_NAME {                                                        \
+  enum {
+#define DIAG_ENUM_ITEM(IDX, NAME) NAME = IDX,
+#define DIAG_ENUM_END()                                                        \
+  }                                                                            \
+  ;                                                                            \
+  }
+#include "clang/Basic/DiagnosticSerializationEnums.inc"
+#undef DIAG_ENUM_END
+#undef DIAG_ENUM_ITEM
+#undef DIAG_ENUM
 } // end namespace diag
 } // end namespace clang
 
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -13217,18 +13217,18 @@ bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc, bool HasTypename,
         if (getLangOpts().CPlusPlus11) {
           // Convert 'using X::Y;' to 'using Y = X::Y;'.
           Diag(SS.getBeginLoc(), diag::note_using_decl_class_member_workaround)
-            << 0 // alias declaration
-            << FixItHint::CreateInsertion(SS.getBeginLoc(),
-                                          NameInfo.getName().getAsString() +
-                                              " = ");
+              << diag::MemClassWorkaround::AliasDecl
+              << FixItHint::CreateInsertion(SS.getBeginLoc(),
+                                            NameInfo.getName().getAsString() +
+                                                " = ");
         } else {
           // Convert 'using X::Y;' to 'typedef X::Y Y;'.
           SourceLocation InsertLoc = getLocForEndOfToken(NameInfo.getEndLoc());
           Diag(InsertLoc, diag::note_using_decl_class_member_workaround)
-            << 1 // typedef declaration
-            << FixItHint::CreateReplacement(UsingLoc, "typedef")
-            << FixItHint::CreateInsertion(
-                   InsertLoc, " " + NameInfo.getName().getAsString());
+              << diag::MemClassWorkaround::TypedefDecl
+              << FixItHint::CreateReplacement(UsingLoc, "typedef")
+              << FixItHint::CreateInsertion(
+                     InsertLoc, " " + NameInfo.getName().getAsString());
         }
       } else if (R->getAsSingle<VarDecl>()) {
         // Don't provide a fixit outside C++11 mode; we don't want to suggest
@@ -13241,8 +13241,7 @@ bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc, bool HasTypename,
         }
 
         Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
-          << 2 // reference declaration
-          << FixIt;
+            << diag::MemClassWorkaround::ReferenceDecl << FixIt;
       } else if (R->getAsSingle<EnumConstantDecl>()) {
         // Don't provide a fixit outside C++11 mode; we don't want to suggest
         // repeating the type of the enumeration here, and we can't do so if
@@ -13256,8 +13255,10 @@ bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc, bool HasTypename,
         }
 
         Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
-          << (getLangOpts().CPlusPlus11 ? 4 : 3) // const[expr] variable
-          << FixIt;
+            << (getLangOpts().CPlusPlus11
+                    ? diag::MemClassWorkaround::ConstexprVar
+                    : diag::MemClassWorkaround::ConstVar)
+            << FixIt;
       }
     }
 
diff --git a/clang/test/TableGen/select-enum-errors.td b/clang/test/TableGen/select-enum-errors.td
@@ -0,0 +1,16 @@
+// RUN: clang-tblgen --gen-clang-diags-enums -I%S %s 2>&1 | FileCheck %s
+include "DiagnosticBase.inc"
+
+def DupeNames1 : Error<"%enum_select<DupeName>{}0">;
+def DupeNames2 : Error<"%enum_select<DupeName>{}0">;
+// CHECK: error: Duplicate enumeration name 'DupeName'
+// CHECK-NEXT: def DupeNames2
+// CHECK: note: Previous diagnostic is here
+// CHECK-NEXT: def DupeNames1
+
+def DupeValue : Error<"%enum_select<DupeValue>{%Name{V1}|%Name{V2}}0">;
+// CHECK: error: Duplicate enumerator name 'Name'
+
+def EnumValNotExpected : Error<"%enum_select{V1|%Val2{V2}}0">;
+// CHECK: expected '<' after enum_select
+
diff --git a/clang/test/TableGen/select-enum.td b/clang/test/TableGen/select-enum.td
@@ -0,0 +1,26 @@
+// RUN: clang-tblgen --gen-clang-diags-enums -I%S %s 2>&1 | FileCheck %s
+include "DiagnosticBase.inc"
+
+def Diag : Error<"%enum_select<EnumName>{%Val1{V1}|%Val2{V2}|%Val3{V3}}0">;
+// CHECK: DIAG_ENUM(EnumName)
+// CHECK-NEXT: DIAG_ENUM_ITEM(0, Val1)
+// CHECK-NEXT: DIAG_ENUM_ITEM(1, Val2)
+// CHECK-NEXT: DIAG_ENUM_ITEM(2, Val3)
+// CHECK-NEXT: DIAG_ENUM_END()
+
+// These are OK, we permit missing values since they might not be useful.
+def Missing1 : Error<"%enum_select<DupeEnumName1>{V1|%Val2{V2}|%Val3{V3}}0">;
+// CHECK: DIAG_ENUM(DupeEnumName1)
+// CHECK-NEXT: DIAG_ENUM_ITEM(1, Val2)
+// CHECK-NEXT: DIAG_ENUM_ITEM(2, Val3)
+// CHECK-NEXT: DIAG_ENUM_END()
+def Missing2 : Error<"%enum_select<DupeEnumName2>{%Val1{V1}|V2|%Val3{V3}}0">;
+// CHECK: DIAG_ENUM(DupeEnumName2)
+// CHECK-NEXT: DIAG_ENUM_ITEM(0, Val1)
+// CHECK-NEXT: DIAG_ENUM_ITEM(2, Val3)
+// CHECK-NEXT: DIAG_ENUM_END()
+def Missing3 : Error<"%enum_select<DupeEnumName3>{%Val1{V1}|%Val2{V2}|V3}0">;
+// CHECK: DIAG_ENUM(DupeEnumName3)
+// CHECK-NEXT: DIAG_ENUM_ITEM(0, Val1)
+// CHECK-NEXT: DIAG_ENUM_ITEM(1, Val2)
+// CHECK-NEXT: DIAG_ENUM_END()
diff --git a/clang/utils/TableGen/ClangDiagnosticsEmitter.cpp b/clang/utils/TableGen/ClangDiagnosticsEmitter.cpp
diff --git a/clang/utils/TableGen/TableGen.cpp b/clang/utils/TableGen/TableGen.cpp
diff --git a/clang/utils/TableGen/TableGenBackends.h b/clang/utils/TableGen/TableGenBackends.h
