diff --git a/mps/code/mps.c b/mps/code/mps.c
index ef2484eabdf..b3be2615c5b 100644
--- a/mps/code/mps.c
+++ b/mps/code/mps.c
@@ -95,9 +95,21 @@
 #include "mpsioan.c"
 #endif
 
+/* ANSI back end. */
+
+#if defined(CONFIG_ANSI)
+
+#include "lockan.c"     /* generic locks */
+#include "than.c"       /* generic threads manager */
+#include "vman.c"       /* malloc-based pseudo memory mapping */
+#include "protan.c"     /* generic memory protection */
+#include "prmcan.c"     /* generic protection mutator context */
+#include "span.c"       /* generic stack probe */
+#include "ssan.c"       /* generic stack scanner */
+
 /* Mac OS X on 32-bit Intel built with Clang or GCC */
 
-#if defined(MPS_PF_XCI3LL) || defined(MPS_PF_XCI3GC)
+#elif defined(MPS_PF_XCI3LL) || defined(MPS_PF_XCI3GC)
 
 #include "lockix.c"     /* Posix locks */
 #include "thxc.c"       /* OS X Mach threading */
diff --git a/mps/code/mps.xcodeproj/project.pbxproj b/mps/code/mps.xcodeproj/project.pbxproj
index d7865d3d4a6..37fb0893447 100644
--- a/mps/code/mps.xcodeproj/project.pbxproj
+++ b/mps/code/mps.xcodeproj/project.pbxproj
@@ -4439,6 +4439,10 @@
 		3114A654156E9596001E0AA3 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				GCC_PREPROCESSOR_DEFINITIONS = (
+					"CONFIG_VAR_COOL=1",
+					"CONFIG_ANSI=1",
+				);
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Debug;
@@ -4523,6 +4527,10 @@
 		3124CAC0156BE3EC00753214 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				GCC_PREPROCESSOR_DEFINITIONS = (
+					CONFIG_VAR_COOL,
+					CONFIG_ANSI,
+				);
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Debug;
diff --git a/mps/code/protan.c b/mps/code/protan.c
index 51b2edd6df8..b9fb46e7062 100644
--- a/mps/code/protan.c
+++ b/mps/code/protan.c
@@ -59,7 +59,7 @@ void ProtSync(Arena arena)
           ShieldLeave(arena);
           synced = FALSE;
         }
-      } while(SegNext(&seg, arena, base));
+      } while(SegNext(&seg, arena, seg));
     }
   } while(!synced);
 }
diff --git a/mps/code/vman.c b/mps/code/vman.c
index db7795c9f2e..2b4f0c3ecb2 100644
--- a/mps/code/vman.c
+++ b/mps/code/vman.c
@@ -63,11 +63,12 @@ Res VMParamFromArgs(void *params, size_t paramSize, ArgList args)
 
 /* VMCreate -- reserve some virtual address space, and create a VM structure */
 
-Res VMCreate(VM *vmReturn, Size size)
+Res VMCreate(VM *vmReturn, Size size, void *params)
 {
   VM vm;
 
   AVER(vmReturn != NULL);
+  AVER(params != NULL);
 
   /* Note that because we add VMANPageALIGNMENT rather than */
   /* VMANPageALIGNMENT-1 we are not in danger of overflowing */