[WebAssembly] objdump: Don't assume all relocations have symbols

Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D46134

llvm-svn: 330959

1 files changed, 6 insertions, 2 deletions

diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index f32ff062c23..0a1f0e2cda7 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -920,10 +920,14 @@ static std::error_code getRelocationValueString(const WasmObjectFile *Obj,
   symbol_iterator SI = RelRef.getSymbol();
   std::string fmtbuf;
   raw_string_ostream fmt(fmtbuf);
-  Expected<StringRef> SymNameOrErr = SI->getName();
-  if (!SymNameOrErr) {
+  if (SI == Obj->symbol_end()) {
+    // Not all wasm relocations have symbols associated with them.
+    // In particular R_WEBASSEMBLY_TYPE_INDEX_LEB.
     fmt << Rel.Index;
   } else {
+    Expected<StringRef> SymNameOrErr = SI->getName();
+    if (!SymNameOrErr)
+      return errorToErrorCode(SymNameOrErr.takeError());
     StringRef SymName = *SymNameOrErr;
     Result.append(SymName.begin(), SymName.end());
   }