uevent_get_env_var() could call condlog with p == NULL. On gcc 10, this triggers warnings like: In file included from uevent.c:47: In function 'uevent_get_env_var', inlined from 'uevent_get_wwid' at uevent.c:170:8: debug.h:13:2: error: '%s' directive argument is null [-Werror=format-overflow=] 13 | dlog(logsink, prio, fmt "\n", ##args) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ uevent.c:132:2: note: in expansion of macro 'condlog' 132 | condlog(4, "%s: %s -> '%s'", __func__, attr, p); | ^~~~~~~ uevent.c: In function 'uevent_get_wwid': uevent.c:132:25: note: format string is defined here 132 | condlog(4, "%s: %s -> '%s'", __func__, attr, p); | ^~ If p is NULL, use "(null)" instead. Signed-off-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx> --- libmultipath/uevent.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libmultipath/uevent.c b/libmultipath/uevent.c index d38e8a7f..e0d13b11 100644 --- a/libmultipath/uevent.c +++ b/libmultipath/uevent.c @@ -129,7 +129,7 @@ static const char* uevent_get_env_var(const struct uevent *uev, } } - condlog(4, "%s: %s -> '%s'", __func__, attr, p); + condlog(4, "%s: %s -> '%s'", __func__, attr, p ?: "(null)"); return p; invalid: -- 2.17.2 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel