--- procps-3.2.5/pmap.c.orig	2005-09-13 23:13:04 +0000
+++ procps-3.2.5/pmap.c	2005-09-13 23:48:34 +0000
@@ -85,10 +85,9 @@ static void discover_shm_minor(void){
     }
   }
 
-  if(shmdt(addr)) perror("shmdt");
-
 out_destroy:
   if(shmctl(shmid, IPC_RMID, NULL)) perror("IPC_RMID");
+  if(addr!=(void*)-1 && shmdt(addr)) perror("shmdt");
 
   return;
 }