diff --git a/llvm/lib/Support/Path.cpp b/llvm/lib/Support/Path.cpp
index 9410252ba3319..c8de2c0625aa2 100644
--- a/llvm/lib/Support/Path.cpp
+++ b/llvm/lib/Support/Path.cpp
@@ -104,7 +104,7 @@ namespace {
 
     if (is_style_windows(style)) {
       if (pos == StringRef::npos)
-        pos = str.find_last_of(':', str.size() - 2);
+        pos = str.find_last_of(':', str.size() - 1);
     }
 
     if (pos == StringRef::npos || (pos == 1 && is_separator(str[0], style)))
diff --git a/llvm/unittests/Support/Path.cpp b/llvm/unittests/Support/Path.cpp
index a7b7e6a0f5044..837ca03216f87 100644
--- a/llvm/unittests/Support/Path.cpp
+++ b/llvm/unittests/Support/Path.cpp
@@ -190,6 +190,7 @@ TEST(Support, Path) {
   paths.push_back("c:\\foo\\");
   paths.push_back("c:\\foo/");
   paths.push_back("c:/foo\\bar");
+  paths.push_back(":");
 
   for (SmallVector<StringRef, 40>::const_iterator i = paths.begin(),
                                                   e = paths.end();