From 3dc215416673f9ba8f136aafbb0069ed9ebff376 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Wed, 9 Jan 2019 21:21:57 -0700 Subject: [PATCH] iavf: Use printf instead of gnu_printf for iavf_debug_d Clang warns: In file included from drivers/net/ethernet/intel/iavf/iavf_main.c:4: In file included from drivers/net/ethernet/intel/iavf/iavf.h:37: In file included from drivers/net/ethernet/intel/iavf/iavf_type.h:8: drivers/net/ethernet/intel/iavf/iavf_osdep.h:49:18: warning: 'format' attribute argument not supported: gnu_printf [-Wignored-attributes] __attribute__ ((format(gnu_printf, 3, 4))); ^ 1 warning generated. We can convert from gnu_printf to printf without any side effects for two reasons: 1. All iavf_debug instances use standard printf formats, as pointed out by Miguel Ojeda at the below link, meaning gnu_printf is not strictly required. 2. However, GCC has aliased printf to gnu_printf on Linux since at least 2010 based on git history. From gcc/c-family/c-format.c: /* Attributes such as "printf" are equivalent to those such as "gnu_printf" unless this is overridden by a target. */ static const target_ovr_attr gnu_target_overrides_format_attributes[] = { { "gnu_printf", "printf" }, { "gnu_scanf", "scanf" }, { "gnu_strftime", "strftime" }, { "gnu_strfmon", "strfmon" }, { NULL, NULL } }; The mentioned override only happens on Windows (mingw32). Changing from gnu_printf to printf is a no-op for GCC and stops Clang from warning. Link: https://github.com/ClangBuiltLinux/linux/issues/111 Suggested-by: Miguel Ojeda Signed-off-by: Nathan Chancellor Reviewed-by: Nick Desaulniers Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/iavf/iavf_osdep.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_osdep.h b/drivers/net/ethernet/intel/iavf/iavf_osdep.h index e6e0b0328706..c90cafb526d0 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_osdep.h +++ b/drivers/net/ethernet/intel/iavf/iavf_osdep.h @@ -46,7 +46,7 @@ struct iavf_virt_mem { #define iavf_debug(h, m, s, ...) iavf_debug_d(h, m, s, ##__VA_ARGS__) extern void iavf_debug_d(void *hw, u32 mask, char *fmt_str, ...) - __attribute__ ((format(gnu_printf, 3, 4))); + __printf(3, 4); typedef enum iavf_status_code iavf_status; #endif /* _IAVF_OSDEP_H_ */ -- 2.30.2