diff --git a/sharedbits/alloc_header.h b/sharedbits/alloc_header.h
index 2a6a414a..0b44d29d 100644
--- a/sharedbits/alloc_header.h
+++ b/sharedbits/alloc_header.h
@@ -4,7 +4,8 @@
 #error you must define sharedbitsPrefix before including this
 #endif
 #define sharedbitsPrefixMakeName(x, y) x ## y
-#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefix, Name)
+#define sharedbitsPrefixExpand(x) x
+#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefixExpand(sharedbitsPrefix), Name)
 
 extern void *sharedbitsPrefixName(Alloc)(size_t n, const char *what);
 extern void *sharedbitsPrefixName(Realloc)(void *p, size_t nOld, size_t nNew, const char *what);
@@ -19,4 +20,5 @@ you may also want to define the following:
 */
 
 #undef sharedbitsPrefixName
+#undef sharedbitsPrefixExpand
 #undef sharedbitsPrefixMakeName
diff --git a/sharedbits/alloc_impl.h b/sharedbits/alloc_impl.h
index e6c194e6..93e5979c 100644
--- a/sharedbits/alloc_impl.h
+++ b/sharedbits/alloc_impl.h
@@ -5,7 +5,8 @@
 #error you must define sharedbitsPrefix before including this
 #endif
 #define sharedbitsPrefixMakeName(x, y) x ## y
-#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefix, Name)
+#define sharedbitsPrefixExpand(x) x
+#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefixExpand(sharedbitsPrefix), Name)
 
 extern void sharedbitsPrefixName(InternalError)(const char *fmt, ...);
 
@@ -36,4 +37,5 @@ void sharedbitsPrefixName(Free)(void *p)
 }
 
 #undef sharedbitsPrefixName
+#undef sharedbitsPrefixExpand
 #undef sharedbitsPrefixMakeName
diff --git a/sharedbits/array_header.h b/sharedbits/array_header.h
index db2ad9f4..6832ac85 100644
--- a/sharedbits/array_header.h
+++ b/sharedbits/array_header.h
@@ -5,7 +5,9 @@
 #error you must define sharedbitsPrefix before including this
 #endif
 #define sharedbitsPrefixMakeName(x, y) x ## y
-#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefix, Name)
+#define sharedbitsPrefixExpand(x) x
+#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefixExpand(sharedbitsPrefix), Name)
 
 #undef sharedbitsPrefixName
+#undef sharedbitsPrefixExpand
 #undef sharedbitsPrefixMakeName
diff --git a/sharedbits/array_impl.h b/sharedbits/array_impl.h
index 1eda47af..a86abbaf 100644
--- a/sharedbits/array_impl.h
+++ b/sharedbits/array_impl.h
@@ -5,7 +5,9 @@
 #error you must define sharedbitsPrefix before including this
 #endif
 #define sharedbitsPrefixMakeName(x, y) x ## y
-#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefix, Name)
+#define sharedbitsPrefixExpand(x) x
+#define sharedbitsPrefixName(Name) sharedbitsPrefixMakeName(sharedbitsPrefixExpand(sharedbitsPrefix), Name)
 
 #undef sharedbitsPrefixName
+#undef sharedbitsPrefixExpand
 #undef sharedbitsPrefixMakeName