fgetflags assigns uninitialized value to *flags (when ioctl fails)

[raforg]

According to valgrind, fgetflags can assign an uninitialized value (f) to *flags. It happens when ioctl fails. For example, this happens for me with /dev/mqueue on Linux.

This patch should fix it. Alternatively, not setting *flags at all when ioctl fails would be another option. That would be better because I expect *flags not to be modified if there's an error. I think most people would expect that.

fgetflags.c-uninitialized.patch

--- fgetflags.c.orig	2026-04-16 11:08:50.000000000 +1000
+++ fgetflags.c	2026-04-16 11:09:15.000000000 +1000
@@ -80,7 +80,7 @@
 	return (save_errno);
 #elif HAVE_EXT2_IOCTLS
 	struct stat buf;
-	int fd, r, f, save_errno = 0;
+	int fd, r, f = 0, save_errno = 0;
 
 	if (!stat(name, &buf) &&
 	    !S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode)) {

or (better):

fgetflags.c-uninitialized.alternate.patch

--- fgetflags.c.orig	2026-04-16 11:08:50.000000000 +1000
+++ fgetflags.c	2026-04-16 11:17:19.000000000 +1000
@@ -105,7 +105,8 @@
 			errno = EOPNOTSUPP;
 		save_errno = errno;
 	}
-	*flags = f;
+	else
+		*flags = f;
 	close(fd);
 	if (save_errno)
 		errno = save_errno;