diff --git a/meson.build b/meson.build
index b879df7b..79aa65e6 100644
--- a/meson.build
+++ b/meson.build
@@ -16,7 +16,7 @@ config_h.set_quoted('PACKAGE', meson.project_name())
 config_h.set_quoted('PACKAGE_VERSION', meson.project_version())
 
 cc_args = []
-if host_machine.system() != 'freebsd'
+if host_machine.system() == 'linux'
 	cc_args += ['-D_POSIX_C_SOURCE=200809L']
 endif
 add_project_arguments(cc_args, language: 'c')
@@ -69,8 +69,8 @@ endif
 config_h.set10('HAVE_BROKEN_MSG_CMSG_CLOEXEC', have_broken_msg_cmsg_cloexec)
 
 if get_option('libraries')
-	if host_machine.system() == 'freebsd'
-		# When building for FreeBSD, epoll(7) is provided by a userspace
+	if cc.has_function('kqueue', prefix: '#include <sys/event.h>')
+		# When building for BSD, epoll(7) is provided by a userspace
 		# wrapper around kqueue(2).
 		epoll_dep = dependency('epoll-shim')
 	else
diff --git a/src/scanner.c b/src/scanner.c
index c512d231..2e9fa3ae 100644
--- a/src/scanner.c
+++ b/src/scanner.c
@@ -294,7 +294,7 @@ uppercase_dup(const char *src)
 
 	u = xstrdup(src);
 	for (i = 0; u[i]; i++)
-		u[i] = toupper(u[i]);
+		u[i] = toupper((unsigned char) u[i]);
 	u[i] = '\0';
 
 	return u;
@@ -354,7 +354,7 @@ desc_dump(char *desc, const char *fmt, ...)
 	for (i = 0; desc[i]; ) {
 		k = i;
 		newlines = 0;
-		while (desc[i] && isspace(desc[i])) {
+		while (desc[i] && isspace((unsigned char) desc[i])) {
 			if (desc[i] == '\n')
 				newlines++;
 			i++;
@@ -363,7 +363,7 @@ desc_dump(char *desc, const char *fmt, ...)
 			break;
 
 		j = i;
-		while (desc[i] && !isspace(desc[i]))
+		while (desc[i] && !isspace((unsigned char) desc[i]))
 			i++;
 
 		if (newlines > 1)
diff --git a/src/wayland-os.c b/src/wayland-os.c
index a0db2e84..3ac0ab16 100644
--- a/src/wayland-os.c
+++ b/src/wayland-os.c
@@ -106,7 +106,25 @@ wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
 #endif
 	return 0;
 }
-#elif defined(SO_PEERCRED)
+#elif defined(LOCAL_CREDS) /* NetBSD */
+#ifndef SOL_LOCAL /* Before NetBSD 10.0, SOL_LOCAL isn't defined */
+#define SOL_LOCAL (0)
+#endif
+int
+wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
+{
+	socklen_t len;
+	struct sockcred ucred;
+
+	len = sizeof(ucred);
+	if (getsockopt(sockfd, SOL_LOCAL, LOCAL_CREDS, &ucred, &len) < 0)
+		return -1;
+	*uid = ucred.sc_uid;
+	*gid = ucred.sc_gid;
+	*pid = ucred.sc_pid;
+	return 0;
+}
+#elif defined(SO_PEERCRED) /* Linux */
 int
 wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
 {
diff --git a/tests/test-runner.c b/tests/test-runner.c
index d07dab15..1bfb0df4 100644
--- a/tests/test-runner.c
+++ b/tests/test-runner.c
@@ -308,6 +308,13 @@ is_debugger_attached(void)
 
 	return rc;
 }
+#else
+static int
+is_debugger_attached(void)
+{
+	/* 0=debugger can't be determined */
+	return 0;
+}
 #endif
 
 int main(int argc, char *argv[])