diff --git a/csrc/vcs_main.ZscaleTestHarness.cc b/csrc/vcs_main.ZscaleTestHarness.cc
new file mode 100644
index 00000000..beb3830d
--- /dev/null
+++ b/csrc/vcs_main.ZscaleTestHarness.cc
@@ -0,0 +1,12 @@
+// See LICENSE for license details.
+
+extern "C" {
+
+extern int vcs_main(int argc, char** argv);
+
+int main(int argc, char** argv)
+{
+  return vcs_main(argc, argv);
+}
+
+}
diff --git a/csrc/vcs_main.cc b/csrc/vcs_main.rocketTestHarness.cc
similarity index 100%
rename from csrc/vcs_main.cc
rename to csrc/vcs_main.rocketTestHarness.cc
diff --git a/fsim/Makefrag b/fsim/Makefrag
index d7087ead..916814c8 100644
--- a/fsim/Makefrag
+++ b/fsim/Makefrag
@@ -15,7 +15,7 @@ sim_vsrcs = \
 # C sources
 
 sim_csrcs = \
-	$(base_dir)/csrc/vcs_main.cc \
+	$(base_dir)/csrc/vcs_main.$(TB).cc \
 	$(base_dir)/csrc/mm.cc \
 	$(base_dir)/csrc/mm_dramsim2.cc \
 
diff --git a/src/main/scala/Configs.scala b/src/main/scala/Configs.scala
index a9e6047e..4ffeac28 100644
--- a/src/main/scala/Configs.scala
+++ b/src/main/scala/Configs.scala
@@ -277,6 +277,7 @@ class DefaultL2FPGAConfig extends Config(new WithL2Capacity64 ++ new WithL2Cache
 class WithZscale extends Config(
   (pname,site,here) => pname match {
     case XLen => 32
+    case UseFPU => false
     case BuildZscale => {
       TestGeneration.addSuites(List(rv32ui("p"), rv32um("p")))
       TestGeneration.addSuites(List(zscaleBmarks))
diff --git a/vsim/Makefrag b/vsim/Makefrag
index 2e7430a6..321c2e93 100644
--- a/vsim/Makefrag
+++ b/vsim/Makefrag
@@ -14,7 +14,7 @@ sim_vsrcs = \
 # C sources
 
 sim_csrcs = \
-	$(base_dir)/csrc/vcs_main.cc \
+	$(base_dir)/csrc/vcs_main.$(TB).cc \
 	$(base_dir)/csrc/mm.cc \
 	$(base_dir)/csrc/mm_dramsim2.cc \