Index: buildbot/osuosl/master/config/builders.py
===================================================================
--- buildbot/osuosl/master/config/builders.py
+++ buildbot/osuosl/master/config/builders.py
@@ -64,6 +64,8 @@
 from zorg.buildbot.builders import ABITestsuitBuilder
 
 from zorg.buildbot.builders import ClangLTOBuilder3Stage
+reload(ClangLTOBuilder3Stage)
+from zorg.buildbot.builders import ClangLTOBuilder3Stage
 
 # Plain LLVM builders.
 def _get_llvm_builders():
@@ -521,8 +523,11 @@
                 clean=True,
                 env=None,
                 build_gold=True,
-                cmake_cache_file="../llvm.src/tools/clang/cmake/caches/3-stage.cmake",
-                extra_cmake_options=["-DLLVM_TARGETS_TO_BUILD=all", "-DLLVM_BINUTILS_INCDIR=/opt/binutils/include"])},
+                cmake_cache_file=["../llvm.src/tools/clang/cmake/caches/3-stage.cmake"],
+                extra_cmake_options=[
+                    "-G", "Ninja",
+                    "-DLLVM_TARGETS_TO_BUILD=all",
+                    "-DLLVM_BINUTILS_INCDIR=/opt/binutils/include"])},
     ]
 
 # Polly builders.
Index: zorg/buildbot/builders/ClangLTOBuilder3Stage.py
===================================================================
--- zorg/buildbot/builders/ClangLTOBuilder3Stage.py
+++ zorg/buildbot/builders/ClangLTOBuilder3Stage.py
@@ -74,7 +74,7 @@
     cmake_command = ["cmake"]
     
     if cmake_cache_file:
-        cmake_command += "-C %s" % (" ".join(cmake_cache_file))
+        cmake_command += ["-C"] + cmake_cache_file
 
     if extra_cmake_options:
         cmake_command += extra_cmake_options