Compiler reports potential uses of uninitialized variables in mptcp_connect.c when xerror() is called from failure paths.
mptcp_connect.c:1262:11: warning: variable 'raw_addr' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
xerror() terminates execution by calling exit(), but it is not visible to the compiler & assumes control flow may continue past the call.
Annotate xerror() with __noreturn so the compiler can correctly reason about control flow and avoid false-positive uninitialized variable warnings.
Signed-off-by: Ankit Khushwaha ankitkhushwaha.linux@gmail.com --- changelog: v3: - also annotate 'die_perror()' with __noreturn - add CFLAGS at top of makefile - target this patch to net instead of net-next as suggested by Matthieu
v2: https://lore.kernel.org/all/20251129043808.16714-1-ankitkhushwaha.linux@gmai... - annotate 'xerror()' with __noreturn - remove defining 'raw_addr' to NULL
v1: https://lore.kernel.org/all/20251126163046.58615-1-ankitkhushwaha.linux@gmai... --- tools/testing/selftests/net/mptcp/Makefile | 1 + tools/testing/selftests/net/mptcp/mptcp_connect.c | 3 ++- tools/testing/selftests/net/mptcp/mptcp_diag.c | 3 ++- tools/testing/selftests/net/mptcp/mptcp_inq.c | 5 +++-- tools/testing/selftests/net/mptcp/mptcp_sockopt.c | 5 +++-- 5 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/net/mptcp/Makefile b/tools/testing/selftests/net/mptcp/Makefile index 15d144a25d82..4dd6278cd3dd 100644 --- a/tools/testing/selftests/net/mptcp/Makefile +++ b/tools/testing/selftests/net/mptcp/Makefile @@ -3,6 +3,7 @@ top_srcdir = ../../../../..
CFLAGS += -Wall -Wl,--no-as-needed -O2 -g -I$(top_srcdir)/usr/include $(KHDR_INCLUDES) +CFLAGS += -I$(top_srcdir)/tools/include
TEST_PROGS := \ diag.sh \ diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c index 404a77bf366a..10f6f99cfd4e 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_connect.c +++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c @@ -33,6 +33,7 @@ #include <linux/tcp.h> #include <linux/time_types.h> #include <linux/sockios.h> +#include <linux/compiler.h>
extern int optind;
@@ -140,7 +141,7 @@ static void die_usage(void) exit(1); }
-static void xerror(const char *fmt, ...) +static void __noreturn xerror(const char *fmt, ...) { va_list ap;
diff --git a/tools/testing/selftests/net/mptcp/mptcp_diag.c b/tools/testing/selftests/net/mptcp/mptcp_diag.c index e084796e804d..8e0b1b8d84b6 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_diag.c +++ b/tools/testing/selftests/net/mptcp/mptcp_diag.c @@ -5,6 +5,7 @@ #include <linux/rtnetlink.h> #include <linux/inet_diag.h> #include <linux/netlink.h> +#include <linux/compiler.h> #include <sys/socket.h> #include <netinet/in.h> #include <linux/tcp.h> @@ -87,7 +88,7 @@ enum {
#define rta_getattr(type, value) (*(type *)RTA_DATA(value))
-static void die_perror(const char *msg) +static void __noreturn die_perror(const char *msg) { perror(msg); exit(1); diff --git a/tools/testing/selftests/net/mptcp/mptcp_inq.c b/tools/testing/selftests/net/mptcp/mptcp_inq.c index 8e8f6441ad8b..5716998da192 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_inq.c +++ b/tools/testing/selftests/net/mptcp/mptcp_inq.c @@ -28,6 +28,7 @@
#include <linux/tcp.h> #include <linux/sockios.h> +#include <linux/compiler.h>
#ifndef IPPROTO_MPTCP #define IPPROTO_MPTCP 262 @@ -40,7 +41,7 @@ static int pf = AF_INET; static int proto_tx = IPPROTO_MPTCP; static int proto_rx = IPPROTO_MPTCP;
-static void die_perror(const char *msg) +static void __noreturn die_perror(const char *msg) { perror(msg); exit(1); @@ -52,7 +53,7 @@ static void die_usage(int r) exit(r); }
-static void xerror(const char *fmt, ...) +static void __noreturn xerror(const char *fmt, ...) { va_list ap;
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c index 286164f7246e..b6e58d936ebe 100644 --- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c +++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c @@ -25,6 +25,7 @@ #include <netinet/in.h>
#include <linux/tcp.h> +#include <linux/compiler.h>
static int pf = AF_INET;
@@ -127,7 +128,7 @@ struct so_state { #define MIN(a, b) ((a) < (b) ? (a) : (b)) #endif
-static void die_perror(const char *msg) +static void __noreturn die_perror(const char *msg) { perror(msg); exit(1); @@ -139,7 +140,7 @@ static void die_usage(int r) exit(r); }
-static void xerror(const char *fmt, ...) +static void __noreturn xerror(const char *fmt, ...) { va_list ap;
-- 2.52.0