diff --git a/lld/include/lld/Common/LLVM.h b/lld/include/lld/Common/LLVM.h
--- a/lld/include/lld/Common/LLVM.h
+++ b/lld/include/lld/Common/LLVM.h
@@ -45,7 +45,6 @@
 
 namespace wasm {
 struct WasmTag;
-struct WasmTagType;
 struct WasmFunction;
 struct WasmGlobal;
 struct WasmGlobalType;
@@ -97,7 +96,6 @@
 using llvm::wasm::WasmTable;
 using llvm::wasm::WasmTableType;
 using llvm::wasm::WasmTag;
-using llvm::wasm::WasmTagType;
 } // end namespace lld.
 
 namespace std {
diff --git a/lld/test/wasm/tag-section.ll b/lld/test/wasm/tag-section.ll
--- a/lld/test/wasm/tag-section.ll
+++ b/lld/test/wasm/tag-section.ll
@@ -30,10 +30,7 @@
 ; CHECK-NEXT:         ReturnTypes:     []
 
 ; CHECK:        - Type:            TAG
-; CHECK-NEXT:     Tags:
-; CHECK-NEXT:       - Index:           0
-; CHECK-NEXT:         Attribute:       0
-; CHECK-NEXT:         SigIndex:        1
+; CHECK-NEXT:     TagTypes:        [ 1 ]
 
 ; Global section has to come after tag section
 ; CHECK:        - Type:            GLOBAL
diff --git a/lld/wasm/InputElement.h b/lld/wasm/InputElement.h
--- a/lld/wasm/InputElement.h
+++ b/lld/wasm/InputElement.h
@@ -74,14 +74,9 @@
 class InputTag : public InputElement {
 public:
   InputTag(const WasmSignature &s, const WasmTag &t, ObjFile *f)
-      : InputElement(t.SymbolName, f), signature(s), type(t.Type) {}
-
-  const WasmTagType &getType() const { return type; }
+      : InputElement(t.SymbolName, f), signature(s) {}
 
   const WasmSignature &signature;
-
-private:
-  WasmTagType type;
 };
 
 class InputTable : public InputElement {
diff --git a/lld/wasm/InputFiles.cpp b/lld/wasm/InputFiles.cpp
--- a/lld/wasm/InputFiles.cpp
+++ b/lld/wasm/InputFiles.cpp
@@ -336,10 +336,9 @@
   LLVM_DEBUG(dbgs() << "Synthesizing symbol for table import: " << info->Name
                     << "\n");
   const WasmGlobalType *globalType = nullptr;
-  const WasmTagType *tagType = nullptr;
   const WasmSignature *signature = nullptr;
-  auto *wasmSym = make<WasmSymbol>(*info, globalType, &tableImport->Table,
-                                   tagType, signature);
+  auto *wasmSym =
+      make<WasmSymbol>(*info, globalType, &tableImport->Table, signature);
   Symbol *sym = createUndefined(*wasmSym, false);
   // We're only sure it's a TableSymbol if the createUndefined succeeded.
   if (errorCount())
@@ -516,7 +515,7 @@
 
   // Populate `Tags`.
   for (const WasmTag &t : wasmObj->tags())
-    tags.emplace_back(make<InputTag>(types[t.Type.SigIndex], t, this));
+    tags.emplace_back(make<InputTag>(types[t.SigIndex], t, this));
 
   // Populate `Symbols` based on the symbols in the object.
   symbols.reserve(wasmObj->getNumberOfSymbols());
diff --git a/lld/wasm/SymbolTable.cpp b/lld/wasm/SymbolTable.cpp
--- a/lld/wasm/SymbolTable.cpp
+++ b/lld/wasm/SymbolTable.cpp
@@ -169,7 +169,6 @@
 }
 
 static void checkTagType(const Symbol *existing, const InputFile *file,
-                         const WasmTagType *newType,
                          const WasmSignature *newSig) {
   const auto *existingTag = dyn_cast<TagSymbol>(existing);
   if (!isa<TagSymbol>(existing)) {
@@ -177,12 +176,7 @@
     return;
   }
 
-  const WasmTagType *oldType = cast<TagSymbol>(existing)->getTagType();
   const WasmSignature *oldSig = existingTag->signature;
-  if (newType->Attribute != oldType->Attribute)
-    error("Tag type mismatch: " + existing->getName() + "\n>>> defined as " +
-          toString(*oldType) + " in " + toString(existing->getFile()) +
-          "\n>>> defined as " + toString(*newType) + " in " + toString(file));
   if (*newSig != *oldSig)
     warn("Tag signature mismatch: " + existing->getName() +
          "\n>>> defined as " + toString(*oldSig) + " in " +
@@ -430,7 +424,7 @@
     return s;
   }
 
-  checkTagType(s, file, &tag->getType(), &tag->signature);
+  checkTagType(s, file, &tag->signature);
 
   if (shouldReplace(s, file, flags))
     replaceSym();
diff --git a/lld/wasm/Symbols.h b/lld/wasm/Symbols.h
--- a/lld/wasm/Symbols.h
+++ b/lld/wasm/Symbols.h
@@ -439,8 +439,6 @@
 public:
   static bool classof(const Symbol *s) { return s->kind() == DefinedTagKind; }
 
-  const WasmTagType *getTagType() const { return tagType; }
-
   // Get/set the tag index
   uint32_t getTagIndex() const;
   void setTagIndex(uint32_t index);
@@ -450,10 +448,9 @@
 
 protected:
   TagSymbol(StringRef name, Kind k, uint32_t flags, InputFile *f,
-            const WasmTagType *tagType, const WasmSignature *sig)
-      : Symbol(name, k, flags, f), signature(sig), tagType(tagType) {}
+            const WasmSignature *sig)
+      : Symbol(name, k, flags, f), signature(sig) {}
 
-  const WasmTagType *tagType;
   uint32_t tagIndex = INVALID_INDEX;
 };
 
diff --git a/lld/wasm/Symbols.cpp b/lld/wasm/Symbols.cpp
--- a/lld/wasm/Symbols.cpp
+++ b/lld/wasm/Symbols.cpp
@@ -369,7 +369,6 @@
 DefinedTag::DefinedTag(StringRef name, uint32_t flags, InputFile *file,
                        InputTag *tag)
     : TagSymbol(name, DefinedTagKind, flags, file,
-                tag ? &tag->getType() : nullptr,
                 tag ? &tag->signature : nullptr),
       tag(tag) {}
 
diff --git a/lld/wasm/SyntheticSections.cpp b/lld/wasm/SyntheticSections.cpp
--- a/lld/wasm/SyntheticSections.cpp
+++ b/lld/wasm/SyntheticSections.cpp
@@ -226,8 +226,7 @@
       import.Global = *globalSym->getGlobalType();
     } else if (auto *tagSym = dyn_cast<TagSymbol>(sym)) {
       import.Kind = WASM_EXTERNAL_TAG;
-      import.Tag.Attribute = tagSym->getTagType()->Attribute;
-      import.Tag.SigIndex = out.typeSec->lookupType(*tagSym->signature);
+      import.SigIndex = out.typeSec->lookupType(*tagSym->signature);
     } else {
       auto *tableSym = cast<TableSymbol>(sym);
       import.Kind = WASM_EXTERNAL_TABLE;
@@ -332,9 +331,8 @@
 
   writeUleb128(os, inputTags.size(), "tag count");
   for (InputTag *t : inputTags) {
-    WasmTagType type = t->getType();
-    type.SigIndex = out.typeSec->lookupType(t->signature);
-    writeTagType(os, type);
+    writeUleb128(os, 0, "tag attribute"); // Reserved "attribute" field
+    writeUleb128(os, out.typeSec->lookupType(t->signature), "sig index");
   }
 }
 
diff --git a/lld/wasm/WriterUtils.h b/lld/wasm/WriterUtils.h
--- a/lld/wasm/WriterUtils.h
+++ b/lld/wasm/WriterUtils.h
@@ -55,10 +55,6 @@
 
 void writeGlobalType(raw_ostream &os, const llvm::wasm::WasmGlobalType &type);
 
-void writeTagType(raw_ostream &os, const llvm::wasm::WasmTagType &type);
-
-void writeTag(raw_ostream &os, const llvm::wasm::WasmTag &tag);
-
 void writeTableType(raw_ostream &os, const llvm::wasm::WasmTableType &type);
 
 void writeImport(raw_ostream &os, const llvm::wasm::WasmImport &import);
@@ -70,7 +66,6 @@
 std::string toString(llvm::wasm::ValType type);
 std::string toString(const llvm::wasm::WasmSignature &sig);
 std::string toString(const llvm::wasm::WasmGlobalType &type);
-std::string toString(const llvm::wasm::WasmTagType &type);
 std::string toString(const llvm::wasm::WasmTableType &type);
 
 } // namespace lld
diff --git a/lld/wasm/WriterUtils.cpp b/lld/wasm/WriterUtils.cpp
--- a/lld/wasm/WriterUtils.cpp
+++ b/lld/wasm/WriterUtils.cpp
@@ -58,12 +58,6 @@
          toString(static_cast<ValType>(type.Type));
 }
 
-std::string toString(const WasmTagType &type) {
-  if (type.Attribute == WASM_TAG_ATTRIBUTE_EXCEPTION)
-    return "exception";
-  return "unknown";
-}
-
 static std::string toString(const llvm::wasm::WasmLimits &limits) {
   std::string ret;
   ret += "flags=0x" + std::to_string(limits.Flags);
@@ -204,15 +198,6 @@
   writeU8(os, type.Mutable, "global mutable");
 }
 
-void writeTagType(raw_ostream &os, const WasmTagType &type) {
-  writeUleb128(os, type.Attribute, "tag attribute");
-  writeUleb128(os, type.SigIndex, "sig index");
-}
-
-void writeTag(raw_ostream &os, const WasmTag &tag) {
-  writeTagType(os, tag.Type);
-}
-
 void writeTableType(raw_ostream &os, const WasmTableType &type) {
   writeValueType(os, ValType(type.ElemType), "table type");
   writeLimits(os, type.Limits);
@@ -230,7 +215,8 @@
     writeGlobalType(os, import.Global);
     break;
   case WASM_EXTERNAL_TAG:
-    writeTagType(os, import.Tag);
+    writeUleb128(os, 0, "tag attribute"); // Reserved "attribute" field
+    writeUleb128(os, import.SigIndex, "import sig index");
     break;
   case WASM_EXTERNAL_MEMORY:
     writeLimits(os, import.Memory);
diff --git a/llvm/include/llvm/BinaryFormat/Wasm.h b/llvm/include/llvm/BinaryFormat/Wasm.h
--- a/llvm/include/llvm/BinaryFormat/Wasm.h
+++ b/llvm/include/llvm/BinaryFormat/Wasm.h
@@ -107,15 +107,9 @@
   StringRef SymbolName; // from the "linking" section
 };
 
-struct WasmTagType {
-  // Kind of tag. Currently only WASM_TAG_ATTRIBUTE_EXCEPTION is possible.
-  uint8_t Attribute;
-  uint32_t SigIndex;
-};
-
 struct WasmTag {
   uint32_t Index;
-  WasmTagType Type;
+  uint32_t SigIndex;
   StringRef SymbolName; // from the "linking" section
 };
 
@@ -128,7 +122,6 @@
     WasmGlobalType Global;
     WasmTableType Table;
     WasmLimits Memory;
-    WasmTagType Tag;
   };
 };
 
diff --git a/llvm/include/llvm/MC/MCSymbolWasm.h b/llvm/include/llvm/MC/MCSymbolWasm.h
--- a/llvm/include/llvm/MC/MCSymbolWasm.h
+++ b/llvm/include/llvm/MC/MCSymbolWasm.h
@@ -27,7 +27,6 @@
   wasm::WasmSignature *Signature = nullptr;
   Optional<wasm::WasmGlobalType> GlobalType;
   Optional<wasm::WasmTableType> TableType;
-  Optional<wasm::WasmTagType> TagType;
 
   /// An expression describing how to calculate the size of a symbol. If a
   /// symbol has no size this field will be NULL.
@@ -147,12 +146,6 @@
     wasm::WasmLimits Limits = {wasm::WASM_LIMITS_FLAG_NONE, 0, 0};
     setTableType({uint8_t(VT), Limits});
   }
-
-  const wasm::WasmTagType &getTagType() const {
-    assert(TagType.hasValue());
-    return TagType.getValue();
-  }
-  void setTagType(wasm::WasmTagType ET) { TagType = ET; }
 };
 
 } // end namespace llvm
diff --git a/llvm/include/llvm/Object/Wasm.h b/llvm/include/llvm/Object/Wasm.h
--- a/llvm/include/llvm/Object/Wasm.h
+++ b/llvm/include/llvm/Object/Wasm.h
@@ -37,15 +37,13 @@
   WasmSymbol(const wasm::WasmSymbolInfo &Info,
              const wasm::WasmGlobalType *GlobalType,
              const wasm::WasmTableType *TableType,
-             const wasm::WasmTagType *TagType,
              const wasm::WasmSignature *Signature)
       : Info(Info), GlobalType(GlobalType), TableType(TableType),
-        TagType(TagType), Signature(Signature) {}
+        Signature(Signature) {}
 
   const wasm::WasmSymbolInfo &Info;
   const wasm::WasmGlobalType *GlobalType;
   const wasm::WasmTableType *TableType;
-  const wasm::WasmTagType *TagType;
   const wasm::WasmSignature *Signature;
 
   bool isTypeFunction() const {
@@ -274,7 +272,6 @@
   wasm::WasmProducerInfo ProducerInfo;
   std::vector<wasm::WasmFeatureEntry> TargetFeatures;
   std::vector<wasm::WasmSignature> Signatures;
-  std::vector<uint32_t> FunctionTypes;
   std::vector<wasm::WasmTable> Tables;
   std::vector<wasm::WasmLimits> Memories;
   std::vector<wasm::WasmGlobal> Globals;
diff --git a/llvm/include/llvm/ObjectYAML/WasmYAML.h b/llvm/include/llvm/ObjectYAML/WasmYAML.h
--- a/llvm/include/llvm/ObjectYAML/WasmYAML.h
+++ b/llvm/include/llvm/ObjectYAML/WasmYAML.h
@@ -77,12 +77,6 @@
   wasm::WasmInitExpr InitExpr;
 };
 
-struct Tag {
-  uint32_t Index;
-  uint32_t Attribute;
-  uint32_t SigIndex;
-};
-
 struct Import {
   StringRef Module;
   StringRef Field;
@@ -92,7 +86,7 @@
     Global GlobalImport;
     Table TableImport;
     Limits Memory;
-    Tag TagImport;
+    uint32_t TagIndex;
   };
 };
 
@@ -329,7 +323,7 @@
     return S->Type == wasm::WASM_SEC_TAG;
   }
 
-  std::vector<Tag> Tags;
+  std::vector<uint32_t> TagTypes;
 };
 
 struct GlobalSection : Section {
@@ -431,7 +425,6 @@
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::WasmYAML::InitFunction)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::WasmYAML::ComdatEntry)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::WasmYAML::Comdat)
-LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::WasmYAML::Tag)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::WasmYAML::DylinkExport)
 
 namespace llvm {
@@ -577,10 +570,6 @@
   static void enumeration(IO &IO, WasmYAML::RelocType &Kind);
 };
 
-template <> struct MappingTraits<WasmYAML::Tag> {
-  static void mapping(IO &IO, WasmYAML::Tag &Tag);
-};
-
 template <> struct MappingTraits<WasmYAML::DylinkExport> {
   static void mapping(IO &IO, WasmYAML::DylinkExport &Export);
 };
diff --git a/llvm/lib/MC/WasmObjectWriter.cpp b/llvm/lib/MC/WasmObjectWriter.cpp
--- a/llvm/lib/MC/WasmObjectWriter.cpp
+++ b/llvm/lib/MC/WasmObjectWriter.cpp
@@ -317,7 +317,7 @@
   uint32_t writeCodeSection(const MCAssembler &Asm, const MCAsmLayout &Layout,
                             ArrayRef<WasmFunction> Functions);
   uint32_t writeDataSection(const MCAsmLayout &Layout);
-  void writeTagSection(ArrayRef<wasm::WasmTagType> Tags);
+  void writeTagSection(ArrayRef<uint32_t> TagTypes);
   void writeGlobalSection(ArrayRef<wasm::WasmGlobal> Globals);
   void writeTableSection(ArrayRef<wasm::WasmTable> Tables);
   void writeRelocSection(uint32_t SectionIndex, StringRef Name,
@@ -831,8 +831,8 @@
       encodeULEB128(NumElements, W->OS); // initial
       break;
     case wasm::WASM_EXTERNAL_TAG:
-      W->OS << char(Import.Tag.Attribute);
-      encodeULEB128(Import.Tag.SigIndex, W->OS);
+      W->OS << char(0); // Reserved 'attribute' field
+      encodeULEB128(Import.SigIndex, W->OS);
       break;
     default:
       llvm_unreachable("unsupported import kind");
@@ -856,17 +856,17 @@
   endSection(Section);
 }
 
-void WasmObjectWriter::writeTagSection(ArrayRef<wasm::WasmTagType> Tags) {
-  if (Tags.empty())
+void WasmObjectWriter::writeTagSection(ArrayRef<uint32_t> TagTypes) {
+  if (TagTypes.empty())
     return;
 
   SectionBookkeeping Section;
   startSection(Section, wasm::WASM_SEC_TAG);
 
-  encodeULEB128(Tags.size(), W->OS);
-  for (const wasm::WasmTagType &Tag : Tags) {
-    W->OS << char(Tag.Attribute);
-    encodeULEB128(Tag.SigIndex, W->OS);
+  encodeULEB128(TagTypes.size(), W->OS);
+  for (uint32_t Index : TagTypes) {
+    W->OS << char(0); // Reserved 'attribute' field
+    encodeULEB128(Index, W->OS);
   }
 
   endSection(Section);
@@ -1346,8 +1346,7 @@
         Import.Module = WS.getImportModule();
         Import.Field = WS.getImportName();
         Import.Kind = wasm::WASM_EXTERNAL_TAG;
-        Import.Tag.Attribute = wasm::WASM_TAG_ATTRIBUTE_EXCEPTION;
-        Import.Tag.SigIndex = getTagType(WS);
+        Import.SigIndex = getTagType(WS);
         Imports.push_back(Import);
         assert(WasmIndices.count(&WS) == 0);
         WasmIndices[&WS] = NumTagImports++;
@@ -1415,7 +1414,7 @@
   SmallVector<uint32_t, 4> TableElems;
   SmallVector<wasm::WasmImport, 4> Imports;
   SmallVector<wasm::WasmExport, 4> Exports;
-  SmallVector<wasm::WasmTagType, 1> Tags;
+  SmallVector<uint32_t, 2> TagTypes;
   SmallVector<wasm::WasmGlobal, 1> Globals;
   SmallVector<wasm::WasmTable, 1> Tables;
   SmallVector<wasm::WasmSymbolInfo, 4> SymbolInfos;
@@ -1654,13 +1653,11 @@
         // (__c_longjmp)
         unsigned Index;
         if (WS.isDefined()) {
-          Index = NumTagImports + Tags.size();
-          wasm::WasmTagType Tag;
-          Tag.SigIndex = getTagType(WS);
-          Tag.Attribute = wasm::WASM_TAG_ATTRIBUTE_EXCEPTION;
+          Index = NumTagImports + TagTypes.size();
+          uint32_t SigIndex = getTagType(WS);
           assert(WasmIndices.count(&WS) == 0);
           WasmIndices[&WS] = Index;
-          Tags.push_back(Tag);
+          TagTypes.push_back(SigIndex);
         } else {
           // An import; the index was assigned above.
           assert(WasmIndices.count(&WS) > 0);
@@ -1878,7 +1875,7 @@
     writeFunctionSection(Functions);
     writeTableSection(Tables);
     // Skip the "memory" section; we import the memory instead.
-    writeTagSection(Tags);
+    writeTagSection(TagTypes);
     writeGlobalSection(Globals);
     writeExportSection(Exports);
     const MCSymbol *IndirectFunctionTable =
diff --git a/llvm/lib/Object/WasmObjectFile.cpp b/llvm/lib/Object/WasmObjectFile.cpp
--- a/llvm/lib/Object/WasmObjectFile.cpp
+++ b/llvm/lib/Object/WasmObjectFile.cpp
@@ -582,7 +582,6 @@
     const wasm::WasmSignature *Signature = nullptr;
     const wasm::WasmGlobalType *GlobalType = nullptr;
     const wasm::WasmTableType *TableType = nullptr;
-    const wasm::WasmTagType *TagType = nullptr;
 
     Info.Kind = readUint8(Ctx);
     Info.Flags = readVaruint32(Ctx);
@@ -727,8 +726,7 @@
         Info.Name = readString(Ctx);
         unsigned TagIndex = Info.ElementIndex - NumImportedTags;
         wasm::WasmTag &Tag = Tags[TagIndex];
-        Signature = &Signatures[Tag.Type.SigIndex];
-        TagType = &Tag.Type;
+        Signature = &Signatures[Tag.SigIndex];
         if (Tag.SymbolName.empty())
           Tag.SymbolName = Info.Name;
 
@@ -740,8 +738,7 @@
         } else {
           Info.Name = Import.Field;
         }
-        TagType = &Import.Tag;
-        Signature = &Signatures[TagType->SigIndex];
+        Signature = &Signatures[Import.SigIndex];
         if (!Import.Module.empty()) {
           Info.ImportModule = Import.Module;
         }
@@ -763,7 +760,7 @@
                                             object_error::parse_failed);
     LinkingData.SymbolTable.emplace_back(Info);
     Symbols.emplace_back(LinkingData.SymbolTable.back(), GlobalType, TableType,
-                         TagType, Signature);
+                         Signature);
     LLVM_DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n");
   }
 
@@ -1090,6 +1087,7 @@
 
 Error WasmObjectFile::parseImportSection(ReadContext &Ctx) {
   uint32_t Count = readVaruint32(Ctx);
+  uint32_t NumTypes = Signatures.size();
   Imports.reserve(Count);
   for (uint32_t I = 0; I < Count; I++) {
     wasm::WasmImport Im;
@@ -1100,6 +1098,9 @@
     case wasm::WASM_EXTERNAL_FUNCTION:
       NumImportedFunctions++;
       Im.SigIndex = readVaruint32(Ctx);
+      if (Im.SigIndex >= NumTypes)
+        return make_error<GenericBinaryError>("invalid function type",
+                                              object_error::parse_failed);
       break;
     case wasm::WASM_EXTERNAL_GLOBAL:
       NumImportedGlobals++;
@@ -1123,8 +1124,10 @@
     }
     case wasm::WASM_EXTERNAL_TAG:
       NumImportedTags++;
-      Im.Tag.Attribute = readUint8(Ctx);
-      Im.Tag.SigIndex = readVarint32(Ctx);
+      Im.SigIndex = readVaruint32(Ctx);
+      if (Im.SigIndex >= NumTypes)
+        return make_error<GenericBinaryError>("invalid tag type",
+                                              object_error::parse_failed);
       break;
     default:
       return make_error<GenericBinaryError>("unexpected import kind",
@@ -1198,11 +1201,19 @@
   TagSection = Sections.size();
   uint32_t Count = readVaruint32(Ctx);
   Tags.reserve(Count);
+  uint32_t NumTypes = Signatures.size();
   while (Count--) {
+    char Attr = readUint8(Ctx); // Reserved 'attribute' field
+    if (Attr != 0)
+      return make_error<GenericBinaryError>("invalid attribute",
+                                            object_error::parse_failed);
+    uint32_t Type = readVaruint32(Ctx);
+    if (Type >= NumTypes)
+      return make_error<GenericBinaryError>("invalid tag type",
+                                            object_error::parse_failed);
     wasm::WasmTag Tag;
     Tag.Index = NumImportedTags + Tags.size();
-    Tag.Type.Attribute = readUint8(Ctx);
-    Tag.Type.SigIndex = readVaruint32(Ctx);
+    Tag.SigIndex = Type;
     Tags.push_back(Tag);
   }
 
diff --git a/llvm/lib/ObjectYAML/WasmEmitter.cpp b/llvm/lib/ObjectYAML/WasmEmitter.cpp
--- a/llvm/lib/ObjectYAML/WasmEmitter.cpp
+++ b/llvm/lib/ObjectYAML/WasmEmitter.cpp
@@ -397,8 +397,8 @@
       NumImportedGlobals++;
       break;
     case wasm::WASM_EXTERNAL_TAG:
-      writeUint32(OS, Import.TagImport.Attribute);
-      writeUint32(OS, Import.TagImport.SigIndex);
+      writeUint8(OS, 0); // Reserved 'attribute' field
+      encodeULEB128(Import.SigIndex, OS);
       NumImportedTags++;
       break;
     case wasm::WASM_EXTERNAL_MEMORY:
@@ -462,16 +462,10 @@
 
 void WasmWriter::writeSectionContent(raw_ostream &OS,
                                      WasmYAML::TagSection &Section) {
-  encodeULEB128(Section.Tags.size(), OS);
-  uint32_t ExpectedIndex = NumImportedTags;
-  for (auto &Tag : Section.Tags) {
-    if (Tag.Index != ExpectedIndex) {
-      reportError("unexpected tag index: " + Twine(Tag.Index));
-      return;
-    }
-    ++ExpectedIndex;
-    encodeULEB128(Tag.Attribute, OS);
-    encodeULEB128(Tag.SigIndex, OS);
+  encodeULEB128(Section.TagTypes.size(), OS);
+  for (uint32_t TagType : Section.TagTypes) {
+    writeUint8(OS, 0); // Reserved 'attribute' field
+    encodeULEB128(TagType, OS);
   }
 }
 
diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp
--- a/llvm/lib/ObjectYAML/WasmYAML.cpp
+++ b/llvm/lib/ObjectYAML/WasmYAML.cpp
@@ -123,7 +123,7 @@
 
 static void sectionMapping(IO &IO, WasmYAML::TagSection &Section) {
   commonSectionMapping(IO, Section);
-  IO.mapOptional("Tags", Section.Tags);
+  IO.mapOptional("TagTypes", Section.TagTypes);
 }
 
 static void sectionMapping(IO &IO, WasmYAML::GlobalSection &Section) {
@@ -392,14 +392,12 @@
   IO.mapRequired("Module", Import.Module);
   IO.mapRequired("Field", Import.Field);
   IO.mapRequired("Kind", Import.Kind);
-  if (Import.Kind == wasm::WASM_EXTERNAL_FUNCTION) {
+  if (Import.Kind == wasm::WASM_EXTERNAL_FUNCTION ||
+      Import.Kind == wasm::WASM_EXTERNAL_TAG) {
     IO.mapRequired("SigIndex", Import.SigIndex);
   } else if (Import.Kind == wasm::WASM_EXTERNAL_GLOBAL) {
     IO.mapRequired("GlobalType", Import.GlobalImport.Type);
     IO.mapRequired("GlobalMutable", Import.GlobalImport.Mutable);
-  } else if (Import.Kind == wasm::WASM_EXTERNAL_TAG) {
-    IO.mapRequired("TagAttribute", Import.TagImport.Attribute);
-    IO.mapRequired("TagSigIndex", Import.TagImport.SigIndex);
   } else if (Import.Kind == wasm::WASM_EXTERNAL_TABLE) {
     IO.mapRequired("Table", Import.TableImport);
   } else if (Import.Kind == wasm::WASM_EXTERNAL_MEMORY) {
@@ -526,12 +524,6 @@
   }
 }
 
-void MappingTraits<WasmYAML::Tag>::mapping(IO &IO, WasmYAML::Tag &Tag) {
-  IO.mapRequired("Index", Tag.Index);
-  IO.mapRequired("Attribute", Tag.Attribute);
-  IO.mapRequired("SigIndex", Tag.SigIndex);
-}
-
 void MappingTraits<WasmYAML::DylinkExport>::mapping(
     IO &IO, WasmYAML::DylinkExport &Export) {
   IO.mapRequired("Name", Export.Name);
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
--- a/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyAsmPrinter.cpp
@@ -238,10 +238,6 @@
   SmallVector<wasm::ValType, 4> Params;
   if (Name == "__cpp_exception" || Name == "__c_longjmp") {
     WasmSym->setType(wasm::WASM_SYMBOL_TYPE_TAG);
-    // We can't confirm its signature index for now because there can be
-    // imported exceptions. Set it to be 0 for now.
-    WasmSym->setTagType(
-        {wasm::WASM_TAG_ATTRIBUTE_EXCEPTION, /* SigIndex */ 0});
     // We may have multiple C++ compilation units to be linked together, each of
     // which defines the exception symbol. To resolve them, we declare them as
     // weak.
diff --git a/llvm/test/MC/WebAssembly/tag-section-decoding.ll b/llvm/test/MC/WebAssembly/tag-section-decoding.ll
--- a/llvm/test/MC/WebAssembly/tag-section-decoding.ll
+++ b/llvm/test/MC/WebAssembly/tag-section-decoding.ll
@@ -339,7 +339,4 @@
 ; number with which its LEB128 and ULEB128 encodings are different, because its
 ; 7th least significant bit is not 0.
 ; CHECK:      - Type:            TAG
-; CHECK-NEXT:   Tags:
-; CHECK-NEXT:     - Index:           0
-; CHECK-NEXT:       Attribute:       0
-; CHECK-NEXT:       SigIndex:        64
+; CHEC-NEXT:    TagTypes:        [ 64 ]
diff --git a/llvm/test/MC/WebAssembly/tag-section.ll b/llvm/test/MC/WebAssembly/tag-section.ll
--- a/llvm/test/MC/WebAssembly/tag-section.ll
+++ b/llvm/test/MC/WebAssembly/tag-section.ll
@@ -29,10 +29,7 @@
 ; CHECK-NEXT:         ReturnTypes:      []
 
 ; CHECK:        - Type:            TAG
-; CHECK-NEXT:     Tags:
-; CHECK-NEXT:       - Index:           0
-; CHECK-NEXT:         Attribute:       0
-; CHECK-NEXT:         SigIndex:        1
+; CHECK-NEXT:     TagTypes:        [ 1 ]
 
 ; CHECK-NEXT:   - Type:            CODE
 ; CHECK-NEXT:     Relocations:
diff --git a/llvm/test/ObjectYAML/wasm/event_section.yaml b/llvm/test/ObjectYAML/wasm/event_section.yaml
--- a/llvm/test/ObjectYAML/wasm/event_section.yaml
+++ b/llvm/test/ObjectYAML/wasm/event_section.yaml
@@ -18,10 +18,7 @@
   - Type:            FUNCTION
     FunctionTypes:   [ 0 ]
   - Type:            TAG
-    Tags:
-      - Index:           0
-        Attribute:       0
-        SigIndex:        1
+    TagTypes:        [ 1 ]
   - Type:            CODE
     Relocations:
       - Type:            R_WASM_TAG_INDEX_LEB
@@ -68,10 +65,7 @@
 # CHECK-NEXT:   - Type:            FUNCTION
 # CHECK-NEXT:     FunctionTypes:   [ 0 ]
 # CHECK-NEXT:   - Type:            TAG
-# CHECK-NEXT:     Tags:
-# CHECK-NEXT:       - Index:           0
-# CHECK-NEXT:         Attribute:       0
-# CHECK-NEXT:         SigIndex:        1
+# CHECK-NEXT:     TagTypes:        [ 1 ]
 # CHECK-NEXT:   - Type:            CODE
 # CHECK-NEXT:     Relocations:
 # CHECK-NEXT:       - Type:            R_WASM_TAG_INDEX_LEB
diff --git a/llvm/tools/obj2yaml/wasm2yaml.cpp b/llvm/tools/obj2yaml/wasm2yaml.cpp
--- a/llvm/tools/obj2yaml/wasm2yaml.cpp
+++ b/llvm/tools/obj2yaml/wasm2yaml.cpp
@@ -241,8 +241,7 @@
           Im.GlobalImport.Mutable = Import.Global.Mutable;
           break;
         case wasm::WASM_EXTERNAL_TAG:
-          Im.TagImport.Attribute = Import.Tag.Attribute;
-          Im.TagImport.SigIndex = Import.Tag.SigIndex;
+          Im.SigIndex = Import.SigIndex;
           break;
         case wasm::WASM_EXTERNAL_TABLE:
           // FIXME: Currently we always output an index of 0 for any imported
@@ -285,11 +284,7 @@
     case wasm::WASM_SEC_TAG: {
       auto TagSec = std::make_unique<WasmYAML::TagSection>();
       for (auto &Tag : Obj.tags()) {
-        WasmYAML::Tag T;
-        T.Index = Tag.Index;
-        T.Attribute = Tag.Type.Attribute;
-        T.SigIndex = Tag.Type.SigIndex;
-        TagSec->Tags.push_back(T);
+        TagSec->TagTypes.push_back(Tag.SigIndex);
       }
       S = std::move(TagSec);
       break;