Index: lld/trunk/COFF/Driver.h
===================================================================
--- lld/trunk/COFF/Driver.h
+++ lld/trunk/COFF/Driver.h
@@ -91,6 +91,7 @@
   // Library search path. The first element is always "" (current directory).
   std::vector<StringRef> SearchPaths;
   std::set<std::string> VisitedFiles;
+  std::set<std::string> VisitedLibs;
 
   SymbolBody *addUndefined(StringRef Sym);
   StringRef mangle(StringRef Sym);
Index: lld/trunk/COFF/Driver.cpp
===================================================================
--- lld/trunk/COFF/Driver.cpp
+++ lld/trunk/COFF/Driver.cpp
@@ -280,11 +280,12 @@
 Optional<StringRef> LinkerDriver::findLib(StringRef Filename) {
   if (Config->NoDefaultLibAll)
     return None;
+  if (!VisitedLibs.insert(Filename.lower()).second)
+    return None;
   StringRef Path = doFindLib(Filename);
   if (Config->NoDefaultLibs.count(Path))
     return None;
-  bool Seen = !VisitedFiles.insert(Path.lower()).second;
-  if (Seen)
+  if (!VisitedFiles.insert(Path.lower()).second)
     return None;
   return Path;
 }