llvm-symbolizer: skip leading underscore in Mach-O symbol table entries

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185151 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-symbolizer/LLVMSymbolize.cpp b/tools/llvm-symbolizer/LLVMSymbolize.cpp
index dfcbacf..5956416 100644
--- a/tools/llvm-symbolizer/LLVMSymbolize.cpp
+++ b/tools/llvm-symbolizer/LLVMSymbolize.cpp
@@ -74,6 +74,9 @@
     StringRef SymbolName;
     if (error(si->getName(SymbolName)))
       continue;
+    // Mach-O symbol table names have leading underscore, skip it.
+    if (Module->isMachO() && SymbolName.size() > 0 && SymbolName[0] == '_')
+      SymbolName = SymbolName.drop_front();
     // FIXME: If a function has alias, there are two entries in symbol table
     // with same address size. Make sure we choose the correct one.
     SymbolMapTy &M = SymbolType == SymbolRef::ST_Function ? Functions : Objects;