From 8d86767be9c9b94f196e663e0ca88e2eb604a20e Mon Sep 17 00:00:00 2001 From: Jiayuan Chen Date: Tue, 11 Mar 2025 19:28:08 +0800 Subject: [PATCH] bpftool: Add -Wformat-signedness flag to detect format errors This commit adds the -Wformat-signedness compiler flag to detect and prevent printf format errors, where signed or unsigned types are mismatched with format specifiers. This helps to catch potential issues at compile-time, ensuring that our code is more robust and reliable. With this flag, the compiler will now warn about incorrect format strings, such as using %d with unsigned types or %u with signed types. Signed-off-by: Jiayuan Chen Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250311112809.81901-2-jiayuan.chen@linux.dev --- tools/bpf/bpftool/Makefile | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile index dd9f3ec842017..efe867dd28215 100644 --- a/tools/bpf/bpftool/Makefile +++ b/tools/bpf/bpftool/Makefile @@ -71,7 +71,12 @@ prefix ?= /usr/local bash_compdir ?= /usr/share/bash-completion/completions CFLAGS += -O2 -CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers +CFLAGS += -W +CFLAGS += -Wall +CFLAGS += -Wextra +CFLAGS += -Wformat-signedness +CFLAGS += -Wno-unused-parameter +CFLAGS += -Wno-missing-field-initializers CFLAGS += $(filter-out -Wswitch-enum -Wnested-externs,$(EXTRA_WARNINGS)) CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \ -I$(or $(OUTPUT),.) \ -- 2.50.1