diff -up libpfm-3.5/examples/multiplex.c.unused libpfm-3.5/examples/multiplex.c
--- libpfm-3.5/examples/multiplex.c.unused	2008-07-31 16:58:21.000000000 -0400
+++ libpfm-3.5/examples/multiplex.c	2008-07-31 16:59:18.000000000 -0400
@@ -613,6 +613,7 @@ measure_one_cpu(char **argv)
 	struct pollfd pollfd;
 	pid_t pid = 0;
 	int ret, timeout;
+	int nbytes;
 
 	memset(ctx, 0, sizeof(ctx));
 	memset(&load_arg, 0, sizeof(load_arg));
@@ -721,7 +722,7 @@ measure_one_cpu(char **argv)
 				 */
 				if (options.opt_ovfl_switch) {
 					pfarg_msg_t msg;
-					read(ctxid, &msg, sizeof(msg));
+					nbytes = read(ctxid, &msg, sizeof(msg));
 				}
 				switch_sets(ctxid);
 				break;
diff -up libpfm-3.5/lib/pfmlib_os_linux.c.unused libpfm-3.5/lib/pfmlib_os_linux.c
--- libpfm-3.5/lib/pfmlib_os_linux.c.unused	2008-07-30 17:16:40.000000000 -0400
+++ libpfm-3.5/lib/pfmlib_os_linux.c	2008-07-31 16:57:05.000000000 -0400
@@ -390,12 +390,13 @@ static int
 pfm_init_syscalls_sysfs(void)
 {
 	FILE *fp;
+	int nbytes;
 
 	fp = fopen("/sys/kernel/perfmon/syscall", "r");
 	if (!fp)
 		return -1;
 
-	fscanf(fp, "%d", &sys_base);
+	nbytes = fscanf(fp, "%d", &sys_base);
 
 	fclose(fp);