+#endif /* !PERL_MEM_LOG_NOIMPL */
+
+#ifndef PERL_MEM_LOG_NOIMPL
+# define \
+ mem_log_common_if(alty, num, tysz, tynm, sv, oal, nal, flnm, ln, fnnm) \
+ mem_log_common (alty, num, tysz, tynm, sv, oal, nal, flnm, ln, fnnm)
+#else
+/* this is suboptimal, but bug compatible. User is providing their
+ own implemenation, but is getting these functions anyway, and they
+ do nothing. But _NOIMPL users should be able to cope or fix */
+# define \
+ mem_log_common_if(alty, num, tysz, tynm, u, oal, nal, flnm, ln, fnnm) \
+ /* mem_log_common_if_PERL_MEM_LOG_NOIMPL */