Down to to compilation errors. Had to reinstate individual size-class headers.

src/c/memory/pso3.h

@@ -0,0 +1,37 @@
+/**
+ *  memory/pso3.h
+ *
+ *  Paged space object of size class 3, 8 words total, 6 words payload.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+#ifndef __psse_memory_pso3_h
+#define __psse_memory_pso3_h
+
+#include <stdint.h>
+
+#include "memory/header.h"
+#include "payloads/exception.h"
+#include "payloads/free.h"
+#include "payloads/mutex.h"
+
+
+/**
+ * @brief A paged space object of size class 3, 8 words total, 6 words
+ * payload.
+ * 
+ */
+struct pso3 {
+    struct pso_header header;
+    union {
+        char bytes[48];
+        uint64_t words[6];
+        struct exception_payload exception;
+        struct free_payload free;
+        struct mutex_payload mutex;
+    } payload;
+};
+
+#endif