diff --git a/puttymem.h b/puttymem.h
index 8fdb8557..e90d7c71 100644
--- a/puttymem.h
+++ b/puttymem.h
@@ -57,4 +57,15 @@ void safefree(void *);
  */
 NORETURN void out_of_memory(void);
 
+#ifdef MINEFIELD
+/*
+ * Definitions for Minefield, PuTTY's own Windows-specific malloc
+ * debugger in the style of Electric Fence. Implemented in winmisc.c,
+ * and referred to by the main malloc wrappers in memory.c.
+ */
+void *minefield_c_malloc(size_t size);
+void minefield_c_free(void *p);
+void *minefield_c_realloc(void *p, size_t size);
+#endif
+
 #endif
diff --git a/windows/winstuff.h b/windows/winstuff.h
index f0daa6ab..2fb2acf6 100644
--- a/windows/winstuff.h
+++ b/windows/winstuff.h
@@ -700,15 +700,4 @@ char *get_jumplist_registry_entries(void);
 #define CLIPUI_DEFAULT_MOUSE CLIPUI_EXPLICIT
 #define CLIPUI_DEFAULT_INS CLIPUI_EXPLICIT
 
-#ifdef MINEFIELD
-/*
- * Definitions for Minefield, PuTTY's own Windows-specific malloc
- * debugger in the style of Electric Fence. Implemented in winmisc.c,
- * and referred to by the main malloc wrappers in memory.c.
- */
-void *minefield_c_malloc(size_t size);
-void minefield_c_free(void *p);
-void *minefield_c_realloc(void *p, size_t size);
-#endif
-
 #endif