Don't dereference target if it is NULL. 

Caught by the clang static analyzer by Jason Molenda.

llvm-svn: 210941
diff --git a/lldb/source/Expression/ClangExpressionDeclMap.cpp b/lldb/source/Expression/ClangExpressionDeclMap.cpp
index 2dee8c8..66673db 100644
--- a/lldb/source/Expression/ClangExpressionDeclMap.cpp
+++ b/lldb/source/Expression/ClangExpressionDeclMap.cpp
@@ -1376,7 +1376,7 @@
                     }
                     else if (sym_ctx.symbol)
                     {
-                        if (sym_ctx.symbol->GetType() == eSymbolTypeReExported)
+                        if (sym_ctx.symbol->GetType() == eSymbolTypeReExported && target)
                         {
                             sym_ctx.symbol = sym_ctx.symbol->ResolveReExportedSymbol(*target);
                             if (sym_ctx.symbol == NULL)