Index: include/parrot/pobj.h
===================================================================
--- include/parrot/pobj.h	(revision 35601)
+++ include/parrot/pobj.h	(working copy)
@@ -55,13 +55,36 @@
 
 #define PObj_bufstart(pmc)    (pmc)->cache._b._bufstart
 #define PObj_buflen(pmc)      (pmc)->cache._b._buflen
+#if 0
 #define PMC_struct_val(pmc)   (pmc)->cache._ptrs._struct_val
 #define PMC_pmc_val(pmc)      (pmc)->cache._ptrs._pmc_val
 #define PMC_int_val(pmc)      (pmc)->cache._i._int_val
 #define PMC_int_val2(pmc)     (pmc)->cache._i._int_val2
 #define PMC_num_val(pmc)      (pmc)->cache._num_val
 #define PMC_str_val(pmc)      (pmc)->cache._string_val
+#else
 
+#define PMC_struct_val(pmc) (((PMC**)pmc)[ instrumenting_func( (long*) &((pmc)->cache._ptrs._struct_val) - (long*)pmc, __LINE__, __FILE__, "PMC_struct_val", WHOAMI(pmc)) ])
+#define PMC_pmc_val(pmc)    (((PMC**)pmc)[ instrumenting_func( (long*) &((pmc)->cache._ptrs._pmc_val)    - (long*)pmc,  __LINE__, __FILE__, "PMC_pmc_val", WHOAMI(pmc)) ])
+#define PMC_int_val(pmc)    (((INTVAL*)pmc)[ instrumenting_func( (long*) &((pmc)->cache._i._int_val)       - (long*)pmc,  __LINE__, __FILE__, "PMC_int_val", WHOAMI(pmc)) ])
+#define PMC_int_val2(pmc)   (((INTVAL*)pmc)[ instrumenting_func( (long*) &((pmc)->cache._i._int_val2)      - (long*)pmc,  __LINE__, __FILE__, "PMC_int_val2", WHOAMI(pmc)) ])
+#define PMC_num_val(pmc)    (((FLOATVAL*)pmc)[ instrumenting_func( (long*) &((pmc)->cache._num_val)          - (long*)pmc,  __LINE__, __FILE__, "PMC_num_val", WHOAMI(pmc)) ])
+#define PMC_str_val(pmc)    (((STRING**)pmc)[ instrumenting_func( (long*) &((pmc)->cache._string_val)       - (long*)pmc,  __LINE__, __FILE__, "PMC_str_val", WHOAMI(pmc)) ])
+
+#define WHOAMI(pmc) ( \
+        ((PMC*)pmc)->vtable != 0xDEADBEEF ? \
+             ((PMC*)pmc)->vtable->whoami->strstart \
+        :NULL )
+
+static inline int instrumenting_func(int, int, const char*, const char*, const char*);
+static inline int instrumenting_func(int ptr, int line, const char *file, const char *macro, const char *pmc_name) {
+    FILE *f = fopen("/tmp/parrot_macro_log","a");
+    fprintf(f, "%s used in %s, %s, line %d\n", pmc_name, macro, file, line);
+    fclose(f);
+    return ptr;
+}
+
+#endif
 /* See src/gc/resources.c. the basic idea is that buffer memory is
    set up as follows:
                     +-----------------+