Otherwise, we get spurious warnings. The compiler should be aware that there is no return from BUG(). Call abort() there, which is marked as __attribute__ ((__noreturn__)). In file included from ./include/nftables.h:6, from ./include/rule.h:4, from src/payload.c:26: src/payload.c: In function 'icmp_dep_to_type': ./include/utils.h:39:34: error: this statement may fall through [-Werror=implicit-fallthrough=] 39 | #define BUG(fmt, arg...) ({ fprintf(stderr, "BUG: " fmt, ##arg); assert(0); }) | ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ src/payload.c:791:17: note: in expansion of macro 'BUG' 791 | BUG("Invalid map for simple dependency"); | ^~~ src/payload.c:792:9: note: here 792 | case PROTO_ICMP_ECHO: return ICMP_ECHO; | ^~~~ Signed-off-by: Thomas Haller <thaller@xxxxxxxxxx> --- include/utils.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/utils.h b/include/utils.h index efc8dec013a1..5b8b181c1e99 100644 --- a/include/utils.h +++ b/include/utils.h @@ -3,6 +3,7 @@ #include <asm/byteorder.h> #include <stdarg.h> +#include <stdlib.h> #include <stdio.h> #include <unistd.h> #include <assert.h> @@ -36,7 +37,7 @@ #define __must_check __attribute__((warn_unused_result)) #define __noreturn __attribute__((__noreturn__)) -#define BUG(fmt, arg...) ({ fprintf(stderr, "BUG: " fmt, ##arg); assert(0); }) +#define BUG(fmt, arg...) ({ fprintf(stderr, "BUG: " fmt, ##arg); assert(0); abort(); }) #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) #define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1) -- 2.41.0