diff --git a/defs.h b/defs.h
index 6c7734ed..a06acde6 100644
--- a/defs.h
+++ b/defs.h
@@ -390,7 +390,7 @@ struct tcb {
 	int flags;		/* See below for TCB_ values */
 	int pid;		/* Process Id of this entry */
 	long scno;		/* System call number */
-	int u_nargs;		/* System call arguments */
+	int u_nargs;		/* System call argument count */
 	long u_arg[MAX_ARGS];	/* System call arguments */
 #if defined (LINUX_MIPSN32)
 	long long ext_arg[MAX_ARGS];	/* System call arguments */
@@ -409,17 +409,19 @@ struct tcb {
 				/* Support for tracing forked processes */
 	long baddr;		/* `Breakpoint' address */
 	long inst[2];		/* Instructions on above */
+	int ptrace_errno;
+#ifdef USE_PROCFS
 	int pfd;		/* proc file descriptor */
+#endif
 #ifdef SVR4
-#ifdef HAVE_MP_PROCFS
+# ifdef HAVE_MP_PROCFS
 	int pfd_stat;
 	int pfd_as;
 	pstatus_t status;
-#else
+# else
 	prstatus_t status;	/* procfs status structure */
+# endif
 #endif
-#endif
-	int ptrace_errno;
 #ifdef FREEBSD
 	struct procfs_status status;
 	int pfd_reg;
diff --git a/strace.c b/strace.c
index 127275c0..7e59b083 100644
--- a/strace.c
+++ b/strace.c
@@ -1256,7 +1256,9 @@ alloc_tcb(int pid, int command_options_parsed)
 			tcp->pid = pid;
 			tcp->flags = TCB_INUSE | TCB_STARTUP;
 			tcp->outf = outf; /* Initialise to current out file */
+#ifdef USE_PROCFS
 			tcp->pfd = -1;
+#endif
 			nprocs++;
 			if (debug)
 				fprintf(stderr, "new tcb for pid %d, active tcbs:%d\n", tcp->pid, nprocs);
@@ -1613,10 +1615,11 @@ droptcb(struct tcb *tcp)
 	if (debug)
 		fprintf(stderr, "dropped tcb for pid %d, %d remain\n", tcp->pid, nprocs);
 
+#ifdef USE_PROCFS
 	if (tcp->pfd != -1) {
 		close(tcp->pfd);
 		tcp->pfd = -1;
-#ifdef FREEBSD
+# ifdef FREEBSD
 		if (tcp->pfd_reg != -1) {
 		        close(tcp->pfd_reg);
 		        tcp->pfd_reg = -1;
@@ -1625,12 +1628,11 @@ droptcb(struct tcb *tcp)
 			close(tcp->pfd_status);
 			tcp->pfd_status = -1;
 		}
-#endif /* !FREEBSD */
-#ifdef USE_PROCFS
+# endif
 		tcp->flags = 0; /* rebuild_pollv needs it */
 		rebuild_pollv();
-#endif
 	}
+#endif
 
 	if (outfname && followfork > 1 && tcp->outf)
 		fclose(tcp->outf);