Index: lib/Driver/ToolChain.cpp
===================================================================
--- lib/Driver/ToolChain.cpp
+++ lib/Driver/ToolChain.cpp
@@ -356,11 +356,17 @@
       TT.isWindowsMSVCEnvironment() || TT.isWindowsItaniumEnvironment();
 
   StringRef Arch = getArchNameForCompilerRTLib(*this, Args);
-  const char *Prefix = IsITANMSVCWindows ? "" : "lib";
-  const char *Suffix = Shared ? (Triple.isOSWindows() ? ".dll" : ".so")
+  const char *Prefix = "-l";
+  const char *Suffix = "";
+  SmallString<128> Path;
+
+  if (getDriver().SysRoot.empty()) {
+    Prefix = IsITANMSVCWindows ? "" : "lib";
+    Suffix = Shared ? (Triple.isOSWindows() ? ".dll" : ".so")
                               : (IsITANMSVCWindows ? ".lib" : ".a");
+    Path = getCompilerRTPath();
+  }
 
-  SmallString<128> Path(getCompilerRTPath());
   llvm::sys::path::append(Path, Prefix + Twine("clang_rt.") + Component + "-" +
                                     Arch + Env + Suffix);
   return Path.str();