really fix PR1581, thanks to Daniel Dunbar for pointing
this out.

llvm-svn: 42448
diff --git a/llvm/lib/System/DynamicLibrary.cpp b/llvm/lib/System/DynamicLibrary.cpp
index a076e3c..b06f6b0 100644
--- a/llvm/lib/System/DynamicLibrary.cpp
+++ b/llvm/lib/System/DynamicLibrary.cpp
@@ -62,7 +62,7 @@
 
   lt_dlhandle a_handle = lt_dlopen(0);
 
-  assert(a_handle == 0 && "Can't open program as dynamic library");
+  assert(a_handle && "Can't open program as dynamic library");
 
   handle = a_handle;
   OpenedHandles.push_back(a_handle);