Index: lld/trunk/test/wasm/alias.ll
===================================================================
--- lld/trunk/test/wasm/alias.ll
+++ lld/trunk/test/wasm/alias.ll
@@ -0,0 +1,66 @@
+; RUN: llc -mtriple=wasm32-unknown-unknown-wasm -filetype=obj -o %t.o %s
+; RUN: lld -flavor wasm %t.o -o %t.wasm
+; RUN: obj2yaml %t.wasm | FileCheck %s
+
+@start_alias = alias i32 (), i32 ()* @_start
+
+; Function Attrs: nounwind uwtable
+define i32 @_start() local_unnamed_addr #1 {
+entry:
+  ret i32 0
+}
+
+; CHECK:      --- !WASM
+; CHECK-NEXT: FileHeader:      
+; CHECK-NEXT:   Version:         0x00000001
+; CHECK-NEXT: Sections:        
+; CHECK-NEXT:   - Type:            TYPE
+; CHECK-NEXT:     Signatures:      
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         ReturnType:      I32
+; CHECK-NEXT:         ParamTypes:      
+; CHECK-NEXT:   - Type:            FUNCTION
+; CHECK-NEXT:     FunctionTypes:   [ 0 ]
+; CHECK-NEXT:   - Type:            TABLE
+; CHECK-NEXT:     Tables:          
+; CHECK-NEXT:       - ElemType:        ANYFUNC
+; CHECK-NEXT:         Limits:          
+; CHECK-NEXT:           Flags:           [ HAS_MAX ]
+; CHECK-NEXT:           Initial:         0x00000001
+; CHECK-NEXT:           Maximum:         0x00000001
+; CHECK-NEXT:   - Type:            MEMORY
+; CHECK-NEXT:     Memories:        
+; CHECK-NEXT:       - Initial:         0x00000002
+; CHECK-NEXT:   - Type:            GLOBAL
+; CHECK-NEXT:     Globals:         
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         Type:            I32
+; CHECK-NEXT:         Mutable:         true
+; CHECK-NEXT:         InitExpr:        
+; CHECK-NEXT:           Opcode:          I32_CONST
+; CHECK-NEXT:           Value:           66560
+; CHECK-NEXT:   - Type:            EXPORT
+; CHECK-NEXT:     Exports:         
+; CHECK-NEXT:       - Name:            memory
+; CHECK-NEXT:         Kind:            MEMORY
+; CHECK-NEXT:         Index:           0
+; CHECK-NEXT:       - Name:            _start
+; CHECK-NEXT:         Kind:            FUNCTION
+; CHECK-NEXT:         Index:           0
+; CHECK-NEXT:       - Name:            start_alias
+; CHECK-NEXT:         Kind:            FUNCTION
+; CHECK-NEXT:         Index:           0
+; CHECK-NEXT:   - Type:            CODE
+; CHECK-NEXT:     Functions:       
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         Locals:          
+; CHECK-NEXT:         Body:            41000B
+; CHECK-NEXT:   - Type:            CUSTOM
+; CHECK-NEXT:     Name:            linking
+; CHECK-NEXT:     DataSize:        0
+; CHECK-NEXT:   - Type:            CUSTOM
+; CHECK-NEXT:     Name:            name
+; CHECK-NEXT:     FunctionNames:   
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         Name:            start_alias
+; CHECK-NEXT: ...
Index: lld/trunk/wasm/InputChunks.h
===================================================================
--- lld/trunk/wasm/InputChunks.h
+++ lld/trunk/wasm/InputChunks.h
@@ -110,7 +110,7 @@
 public:
   InputFunction(const WasmSignature &S, const WasmFunction &Func,
                 const ObjFile &F)
-      : InputChunk(F), Signature(S), Function(Func) {}
+      : InputChunk(F), Signature(S), WrittenToNameSec(false), Function(Func) {}
 
   uint32_t getSize() const override { return Function.Size; }
   const uint8_t *getData() const override {
@@ -126,6 +126,8 @@
 
   const WasmSignature &Signature;
 
+  unsigned WrittenToNameSec : 1;
+
 protected:
   uint32_t getInputSectionOffset() const override {
     return Function.CodeSectionOffset;
Index: lld/trunk/wasm/Symbols.h
===================================================================
--- lld/trunk/wasm/Symbols.h
+++ lld/trunk/wasm/Symbols.h
@@ -93,11 +93,11 @@
 
   void update(Kind K, InputFile *F = nullptr, uint32_t Flags = 0,
               const InputSegment *Segment = nullptr,
-              const InputFunction *Function = nullptr,
-              uint32_t Address = UINT32_MAX);
+              InputFunction *Function = nullptr, uint32_t Address = UINT32_MAX);
 
   void setArchiveSymbol(const Archive::Symbol &Sym) { ArchiveSymbol = Sym; }
   const Archive::Symbol &getArchiveSymbol() { return ArchiveSymbol; }
+  InputFunction *getFunction() { return Function; }
 
   // This bit is used by Writer::writeNameSection() to prevent
   // symbols from being written to the symbol table more than once.
@@ -113,7 +113,7 @@
   Kind SymbolKind = InvalidKind;
   InputFile *File = nullptr;
   const InputSegment *Segment = nullptr;
-  const InputFunction *Function = nullptr;
+  InputFunction *Function = nullptr;
   llvm::Optional<uint32_t> OutputIndex;
   llvm::Optional<uint32_t> TableIndex;
   const WasmSignature *FunctionType = nullptr;
Index: lld/trunk/wasm/Symbols.cpp
===================================================================
--- lld/trunk/wasm/Symbols.cpp
+++ lld/trunk/wasm/Symbols.cpp
@@ -74,7 +74,7 @@
 }
 
 void Symbol::update(Kind K, InputFile *F, uint32_t Flags_,
-                    const InputSegment *Seg, const InputFunction *Func,
+                    const InputSegment *Seg, InputFunction *Func,
                     uint32_t Address) {
   SymbolKind = K;
   File = F;
Index: lld/trunk/wasm/Writer.cpp
===================================================================
--- lld/trunk/wasm/Writer.cpp
+++ lld/trunk/wasm/Writer.cpp
@@ -442,6 +442,15 @@
     for (Symbol *S : File->getSymbols()) {
       if (!S->isFunction() || S->isWeak() || S->WrittenToNameSec)
         continue;
+      // We also need to guard against two different symbols (two different
+      // names) for the same wasm function.  While this is possible (aliases)
+      // it is not legal in the "name" section.
+      InputFunction *Function = S->getFunction();
+      if (Function) {
+        if (Function->WrittenToNameSec)
+          continue;
+        Function->WrittenToNameSec = true;
+      }
       S->WrittenToNameSec = true;
       Names.emplace_back(S);
     }