Index: ELF/SymbolTable.cpp
===================================================================
--- ELF/SymbolTable.cpp
+++ ELF/SymbolTable.cpp
@@ -495,7 +495,11 @@
   if (WasInserted || ((S->isUndefined() || S->isLazy()) &&
                       S->getVisibility() == STV_DEFAULT)) {
     uint8_t Binding = S->Binding;
-    replaceSymbol<SharedSymbol>(S, File, Name, Sym.getBinding(), Sym.st_other,
+    uint8_t OrigBinding = Sym.getBinding();
+    if (OrigBinding == STB_LOCAL)
+      error("Found local symbol '" + Name +
+            "' in global part of symbol table in file " + toString(File));
+    replaceSymbol<SharedSymbol>(S, File, Name, OrigBinding, Sym.st_other,
                                 Sym.getType(), Sym.st_value, Sym.st_size,
                                 Alignment, VerdefIndex);
     if (!WasInserted) {
Index: test/ELF/invalid-local-symbol-in-dso.s
===================================================================
--- /dev/null
+++ test/ELF/invalid-local-symbol-in-dso.s
@@ -0,0 +1,5 @@
+# RUN: llvm-mc %s -o %t.o -filetype=obj -triple x86_64-pc-linux
+
+# We used to crash on this
+# RUN: not ld.lld %t.o %p/Inputs/local-symbol-in-dso.so -o %t 2>&1 | FileCheck %s
+# CHECK: Found local symbol 'foo' in global part of symbol table in file {{.*}}local-symbol-in-dso.so