diff --git a/test/lit.cfg b/test/lit.cfg
index 9a4cfa4d388..9a2f74c21c9 100644
--- a/test/lit.cfg
+++ b/test/lit.cfg
@@ -175,6 +175,10 @@ for sub in ['llvmgcc', 'llvmgxx', 'emitir', 'compile_cxx', 'compile_c',
 # (llvm_tools_dir in lit parlance).
                 # Don't match 'bugpoint-' or 'clang-'.
                                         # Don't match '/clang'.
+if os.pathsep == ';':
+    pathext = os.environ.get('PATHEXT', '').split(';')
+else:
+    pathext = ['']
 for pattern in [r"\bbugpoint\b(?!-)",   r"(?<!/)\bclang\b(?!-)",
                 r"\bgold\b",
                 r"\bllc\b",             r"\blli\b",
@@ -204,6 +208,11 @@ for pattern in [r"\bbugpoint\b(?!-)",   r"(?<!/)\bclang\b(?!-)",
     substitution = re.sub(r"^(\\)?((\| )?)\W+b([0-9A-Za-z-_]+)\\b\W*$",
                           r"\2" + llvm_tools_dir + "/" + r"\4",
                           pattern)
+    for ext in pathext:
+        substitution_ext = substitution + ext
+        if os.path.exists(substitution_ext):
+             substitution = substitution_ext
+             break
     config.substitutions.append((pattern, substitution))
 
 excludes = []