From c1d84ca68b40c115681671eb7630648a548d1c35 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Tue, 21 Jan 2025 18:11:33 -0700 Subject: [PATCH 1/3] x86/boot: Use '-std=gnu11' to fix build with GCC 15 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hulk inclusion category: fix bugzilla: https://gitee.com/openeuler/kernel/issues/ICCAAS ------------------------------------------------- GCC 15 changed the default C standard version to C23, which should not have impacted the kernel because it requests the gnu11 standard via '-std=' in the main Makefile. However, the x86 compressed boot Makefile uses its own set of KBUILD_CFLAGS without a '-std=' value (i.e., using the default), resulting in errors from the kernel's definitions of bool, true, and false in stddef.h, which are reserved keywords under C23. ./include/linux/stddef.h:11:9: error: expected identifier before ‘false’ 11 | false = 0, ./include/linux/types.h:35:33: error: two or more data types in declaration specifiers 35 | typedef _Bool bool; Set '-std=gnu11' in the x86 compressed boot Makefile to resolve the error and consistently use the same C standard version for the entire kernel. Closes: https://lore.kernel.org/4OAhbllK7x4QJGpZjkYjtBYNLd_2whHx9oFiuZcGwtVR4hIzvduultkgfAIRZI3vQpZylu7Gl929HaYFRGeMEalWCpeMzCIIhLxxRhq4U-Y=@protonmail.com/ Closes: https://lore.kernel.org/Z4467umXR2PZ0M1H@tucnak/ Reported-by: Kostadin Shishmanov Reported-by: Jakub Jelinek Signed-off-by: Nathan Chancellor Signed-off-by: Dave Hansen Reviewed-by: Ard Biesheuvel Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/20250121-x86-use-std-consistently-gcc-15-v1-1-8ab0acf645cb%40kernel.org --- arch/x86/boot/compressed/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 5b7de8c8be8d..29ad1307355c 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -34,6 +34,7 @@ targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \ # avoid errors with '-march=i386', and future flags may depend on the target to # be valid. KBUILD_CFLAGS := -m$(BITS) -O2 $(CLANG_FLAGS) +KBUILD_CFLAGS += -std=gnu11 KBUILD_CFLAGS += -fno-strict-aliasing -fPIE KBUILD_CFLAGS += -Wundef KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING -- Gitee From 42f9a7adba40e99e071793d2e150391c96a9f20f Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Tue, 21 Jan 2025 18:11:34 -0700 Subject: [PATCH 2/3] efi: libstub: Use '-std=gnu11' to fix build with GCC 15 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hulk inclusion category: fix bugzilla: https://gitee.com/openeuler/kernel/issues/ICCAAS ------------------------------------------------- GCC 15 changed the default C standard version to C23, which should not have impacted the kernel because it requests the gnu11 standard via '-std=' in the main Makefile. However, the EFI libstub Makefile uses its own set of KBUILD_CFLAGS for x86 without a '-std=' value (i.e., using the default), resulting in errors from the kernel's definitions of bool, true, and false in stddef.h, which are reserved keywords under C23. ./include/linux/stddef.h:11:9: error: expected identifier before ‘false’ 11 | false = 0, ./include/linux/types.h:35:33: error: two or more data types in declaration specifiers 35 | typedef _Bool bool; Set '-std=gnu11' in the x86 cflags to resolve the error and consistently use the same C standard version for the entire kernel. All other architectures reuse KBUILD_CFLAGS from the rest of the kernel, so this issue is not visible for them. Cc: stable@vger.kernel.org Reported-by: Kostadin Shishmanov Closes: https://lore.kernel.org/4OAhbllK7x4QJGpZjkYjtBYNLd_2whHx9oFiuZcGwtVR4hIzvduultkgfAIRZI3vQpZylu7Gl929HaYFRGeMEalWCpeMzCIIhLxxRhq4U-Y=@protonmail.com/ Reported-by: Jakub Jelinek Closes: https://lore.kernel.org/Z4467umXR2PZ0M1H@tucnak/ Signed-off-by: Nathan Chancellor Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 1b87a67366c9..da8eac6dfc0f 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -11,7 +11,7 @@ cflags-y := $(KBUILD_CFLAGS) cflags-$(CONFIG_X86_32) := -march=i386 cflags-$(CONFIG_X86_64) := -mcmodel=small -cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ \ +cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ -std=gnu11 \ -fPIC -fno-strict-aliasing -mno-red-zone \ -mno-mmx -mno-sse -fshort-wchar \ -Wno-pointer-sign \ -- Gitee From 32b3266bfaa2a6e73ca68e1fc8e67ddca0be8ce8 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Wed, 27 Sep 2023 18:42:11 +0300 Subject: [PATCH 3/3] x86/boot: Compile boot code with -std=gnu11 too hulk inclusion category: fix bugzilla: https://gitee.com/openeuler/kernel/issues/ICCAAS ------------------------------------------------- Use -std=gnu11 for consistency with main kernel code. It doesn't seem to change anything in vmlinux. Signed-off-by: Alexey Dobriyan Signed-off-by: Ingo Molnar Acked-by: H. Peter Anvin (Intel) Link: https://lore.kernel.org/r/2058761e-12a4-4b2f-9690-3c3c1c9902a5@p183 --- arch/x86/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 5bfe5caaa444..776331f3f9c3 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -43,7 +43,7 @@ endif # How to compile the 16-bit code. Note we always compile for -march=i386; # that way we can complain to the user if the CPU is insufficient. -REALMODE_CFLAGS := -m16 -g -Os -DDISABLE_BRANCH_PROFILING -D__DISABLE_EXPORTS \ +REALMODE_CFLAGS := -std=gnu11 -m16 -g -Os -DDISABLE_BRANCH_PROFILING -D__DISABLE_EXPORTS \ -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \ -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ -mno-mmx -mno-sse $(call cc-option,-fcf-protection=none) -- Gitee