From 53dc8ae66c5ca8dac65bd6f51c0cbb8b0d22aa2a Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 29 Nov 2019 19:47:59 +0200 Subject: [PATCH] gcc-9: silence 'address-of-packed-member' warning MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit GCC 9.x starts complaining about potential misalignment of the pointer to the array (in this case alignment=2) in the packed (alignment=1) structures. Repeating Linus' Torvalds commit 6f303d60534c in the Linux kernel. Original commit message: We already did this for clang, but now gcc has that warning too. Yes, yes, the address may be unaligned. And that's kind of the point. This in particular hides the warnings like drivers/usb/gadget/composite.c:545:23: warning: taking address of packed member of ‘struct usb_string_descriptor’ may result in an unaligned pointer value [-Waddress-of-packed-member] 545 | collect_langs(sp, s->wData); drivers/usb/gadget/composite.c:550:24: warning: taking address of packed member of ‘struct usb_string_descriptor’ may result in an unaligned pointer value [-Waddress-of-packed-member] 550 | collect_langs(sp, s->wData); drivers/usb/gadget/composite.c:555:25: warning: taking address of packed member of ‘struct usb_string_descriptor’ may result in an unaligned pointer value [-Waddress-of-packed-member] 555 | collect_langs(sp, s->wData); Signed-off-by: Andy Shevchenko --- Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index cc126ebc53..3f332e6885 100644 --- a/Makefile +++ b/Makefile @@ -672,11 +672,12 @@ endif endif KBUILD_CFLAGS += $(call cc-option,-Wno-format-nonliteral) +KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) + ifeq ($(cc-name),clang) KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier) KBUILD_CFLAGS += $(call cc-disable-warning, gnu) -KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior) endif -- 2.39.5