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
@@ -470,8 +470,8 @@
   return LHS.ElemType == RHS.ElemType && LHS.Limits == RHS.Limits;
 }
 
-std::string toString(WasmSymbolType type);
-std::string relocTypetoString(uint32_t type);
+llvm::StringRef toString(WasmSymbolType type);
+llvm::StringRef relocTypetoString(uint32_t type);
 llvm::StringRef sectionTypeToString(uint32_t type);
 bool relocTypeHasAddend(uint32_t type);
 
diff --git a/llvm/lib/BinaryFormat/Wasm.cpp b/llvm/lib/BinaryFormat/Wasm.cpp
--- a/llvm/lib/BinaryFormat/Wasm.cpp
+++ b/llvm/lib/BinaryFormat/Wasm.cpp
@@ -8,7 +8,7 @@
 
 #include "llvm/BinaryFormat/Wasm.h"
 
-std::string llvm::wasm::toString(wasm::WasmSymbolType Type) {
+llvm::StringRef llvm::wasm::toString(wasm::WasmSymbolType Type) {
   switch (Type) {
   case wasm::WASM_SYMBOL_TYPE_FUNCTION:
     return "WASM_SYMBOL_TYPE_FUNCTION";
@@ -26,7 +26,7 @@
   llvm_unreachable("unknown symbol type");
 }
 
-std::string llvm::wasm::relocTypetoString(uint32_t Type) {
+llvm::StringRef llvm::wasm::relocTypetoString(uint32_t Type) {
   switch (Type) {
 #define WASM_RELOC(NAME, VALUE)                                                \
   case VALUE:                                                                  \