basic/socket-util: add hint to silence gcc's maybe-unitialized warning

[59/1551] Compiling C object src/basic/libbasic.a.p/socket-util.c.o
../src/basic/socket-util.c: In function ‘socket_get_mtu’:
../src/basic/socket-util.c:1393:16: warning: ‘mtu’ may be used uninitialized in this function [-Wmaybe-uninitialized]
 1393 |         *ret = (size_t) mtu;
      |                ^~~~~~~~~~~~

diff --git a/src/basic/socket-util.h b/src/basic/socket-util.h
index 507a599d7cfa072833b1364d2e55f4ff45ca5abf..e0b959f5da550cc1bd60c430bc64bee179fe5561 100644 (file)
--- a/src/basic/socket-util.h
+++ b/src/basic/socket-util.h
@@ -14,6 +14,7 @@
 #include <sys/types.h>
 #include <sys/un.h>
 
+#include "errno-util.h"
 #include "macro.h"
 #include "missing_network.h"
 #include "missing_socket.h"
@@ -264,7 +265,7 @@ static inline int getsockopt_int(int fd, int level, int optname, int *ret) {
         socklen_t sl = sizeof(v);
 
         if (getsockopt(fd, level, optname, &v, &sl) < 0)
-                return -errno;
+                return negative_errno();
         if (sl != sizeof(v))
                 return -EIO;