diff --git a/tests/sys/kern/module_test.c b/tests/sys/kern/module_test.c
index eaebf7196523..37cbc3b3271a 100644
--- a/tests/sys/kern/module_test.c
+++ b/tests/sys/kern/module_test.c
@@ -1,197 +1,197 @@
 /*-
  * Copyright (c) 2022 University of Cambridge
  *
  * This software was developed by Ararat River Consulting, LLC under
  * sponsorship from the University of Cambridge Computer Laboratory
  * (Department of Computer Science and Technology) and Google, Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
 #include <sys/param.h>
 #include <sys/module.h>
 #include <errno.h>
 #include <atf-c.h>
 
 ATF_TC_WITHOUT_HEAD(modfind);
 ATF_TC_BODY(modfind, tc)
 {
 	int modid;
 
 	/* This module is present in sys/kern/subr_bus.c. */
 	modid = modfind("rootbus");
 	ATF_REQUIRE(modid > 0);
 
 	modid = modfind("nonexistent_module");
 	ATF_REQUIRE(modid == -1);
-	ATF_REQUIRE(errno = ENOENT);
+	ATF_REQUIRE(errno == ENOENT);
 }
 
 ATF_TC_WITHOUT_HEAD(modnext);
 ATF_TC_BODY(modnext, tc)
 {
 	int modid;
 
 	/* This assumes -1 is never used as a valid module id. */
 	modid = modnext(-1);
 	ATF_REQUIRE(modid == -1);
-	ATF_REQUIRE(errno = ENOENT);
+	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modnext(0);
 	ATF_REQUIRE(modid > 0);
 
 	for (;;) {
 		modid = modnext(modid);
 		ATF_REQUIRE(modid >= 0);
 		if (modid == 0)
 			break;
 	}
 }
 
 ATF_TC_WITHOUT_HEAD(modfnext);
 ATF_TC_BODY(modfnext, tc)
 {
 	int modid;
 
 	/* This assumes -1 is never used as a valid module id. */
 	modid = modfnext(-1);
 	ATF_REQUIRE(modid == -1);
-	ATF_REQUIRE(errno = ENOENT);
+	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modfnext(0);
 	ATF_REQUIRE(modid == -1);
-	ATF_REQUIRE(errno = ENOENT);
+	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modnext(0);
 	ATF_REQUIRE(modid > 0);
 
 	for (;;) {
 		modid = modfnext(modid);
 		ATF_REQUIRE(modid >= 0);
 		if (modid == 0)
 			break;
 	}
 }
 
 ATF_TC_WITHOUT_HEAD(modstat);
 ATF_TC_BODY(modstat, tc)
 {
 	struct module_stat ms;
 	int modid;
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(0, &ms) == -1);
 	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modnext(0);
 	ATF_REQUIRE(modid > 0);
 
 	ATF_REQUIRE(modstat(modid, NULL) == -1);
 	ATF_REQUIRE(errno == EFAULT);
 
 	ms.version = 0;
 	ATF_REQUIRE(modstat(modid, &ms) == -1);
 	ATF_REQUIRE(errno == EINVAL);
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(modid, &ms) == 0);
 	ATF_REQUIRE(ms.id == modid);
 	if (strnlen(ms.name, sizeof(ms.name)) < sizeof(ms.name))
 		ATF_REQUIRE(modfind(ms.name) == modid);
 }
 
 ATF_TC_WITHOUT_HEAD(modstat_v1);
 ATF_TC_BODY(modstat_v1, tc)
 {
 	struct module_stat_v1 {
 		int	version;
 		char	name[32];
 		int	refs;
 		int	id;
 	} ms;
 	int modid;
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(0, (struct module_stat *)&ms) == -1);
 	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modnext(0);
 	ATF_REQUIRE(modid > 0);
 
 	ATF_REQUIRE(modstat(modid, NULL) == -1);
 	ATF_REQUIRE(errno == EFAULT);
 
 	ms.version = 0;
 	ATF_REQUIRE(modstat(modid, (struct module_stat *)&ms) == -1);
 	ATF_REQUIRE(errno == EINVAL);
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(modid, (struct module_stat *)&ms) == 0);
 	ATF_REQUIRE(ms.id == modid);
 	if (strnlen(ms.name, sizeof(ms.name)) < sizeof(ms.name))
 		ATF_REQUIRE(modfind(ms.name) == modid);
 }
 
 ATF_TC_WITHOUT_HEAD(modstat_v2);
 ATF_TC_BODY(modstat_v2, tc)
 {
 	struct module_stat_v2 {
 		int	version;
 		char	name[32];
 		int	refs;
 		int	id;
 		modspecific_t data;
 	} ms;
 	int modid;
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(0, (struct module_stat *)&ms) == -1);
 	ATF_REQUIRE(errno == ENOENT);
 
 	modid = modnext(0);
 	ATF_REQUIRE(modid > 0);
 
 	ATF_REQUIRE(modstat(modid, NULL) == -1);
 	ATF_REQUIRE(errno == EFAULT);
 
 	ms.version = 0;
 	ATF_REQUIRE(modstat(modid, (struct module_stat *)&ms) == -1);
 	ATF_REQUIRE(errno == EINVAL);
 
 	ms.version = sizeof(ms);
 	ATF_REQUIRE(modstat(modid, (struct module_stat *)&ms) == 0);
 	ATF_REQUIRE(ms.id == modid);
 	if (strnlen(ms.name, sizeof(ms.name)) < sizeof(ms.name))
 		ATF_REQUIRE(modfind(ms.name) == modid);
 }
 
 ATF_TP_ADD_TCS(tp)
 {
 	ATF_TP_ADD_TC(tp, modfind);
 	ATF_TP_ADD_TC(tp, modnext);
 	ATF_TP_ADD_TC(tp, modfnext);
 	ATF_TP_ADD_TC(tp, modstat);
 	ATF_TP_ADD_TC(tp, modstat_v1);
 	ATF_TP_ADD_TC(tp, modstat_v2);
 
 	return (atf_no_error());
 }