Change \u which is causing a syntax error.  I'm not sure if that should be, but
at least this should let the build get farther on amd64 machines.
diff --git a/PCbuild/build_ssl.py b/PCbuild/build_ssl.py
index f24c906..7f3a5d0 100644
--- a/PCbuild/build_ssl.py
+++ b/PCbuild/build_ssl.py
@@ -233,7 +233,7 @@
 
         # Now run make.
         if arch == "amd64":
-            rc = os.system(r"ml64 -c -Foms\uptable.obj ms\uptable.asm")
+            rc = os.system("ml64 -c -Foms\\uptable.obj ms\\uptable.asm")
             if rc:
                 print("ml64 assembler has failed.")
                 sys.exit(rc)