* [tip: x86/urgent] x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
@ 2019-08-28 10:09 tip-bot2 for Ingo Molnar
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Ingo Molnar @ 2019-08-28 10:09 UTC (permalink / raw)
To: linux-tip-commits
Cc: Linus Torvalds, Borislav Petkov, Peter Zijlstra, Thomas Gleixner,
Ingo Molnar, linux-kernel
The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: 183e6429186150690cee034eb85745cf2b15ccb4
Gitweb: https://git.kernel.org/tip/183e6429186150690cee034eb85745cf2b15ccb4
Author: Ingo Molnar <mingo@kernel.org>
AuthorDate: Wed, 28 Aug 2019 10:56:48 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 28 Aug 2019 10:58:41 +02:00
x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
One of the very few warnings I have in the current build comes from
arch/x86/boot/edd.c, where I get the following with a gcc9 build:
arch/x86/boot/edd.c: In function ‘query_edd’:
arch/x86/boot/edd.c:148:11: warning: taking address of packed member of ‘struct boot_params’ may result in an unaligned pointer value [-Waddress-of-packed-member]
148 | mbrptr = boot_params.edd_mbr_sig_buffer;
| ^~~~~~~~~~~
This warning triggers because we throw away all the CFLAGS and then make
a new set for REALMODE_CFLAGS, so the -Wno-address-of-packed-member we
added in the following commit is not present:
6f303d60534c ("gcc-9: silence 'address-of-packed-member' warning")
The simplest solution for now is to adjust the warning for this version
of CFLAGS as well, but it would definitely make sense to examine whether
REALMODE_CFLAGS could be derived from CFLAGS, so that it picks up changes
in the compiler flags environment automatically.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 56e748a..94df086 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -38,6 +38,7 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)
+REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member)
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
export REALMODE_CFLAGS
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [tip: x86/urgent] x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
@ 2019-08-28 16:09 tip-bot2 for Linus Torvalds
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Linus Torvalds @ 2019-08-28 16:09 UTC (permalink / raw)
To: linux-tip-commits
Cc: Linus Torvalds, Borislav Petkov, Peter Zijlstra, Thomas Gleixner,
Ingo Molnar, linux-kernel
The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: 42e0e95474fc6076b5cd68cab8fa0340a1797a72
Gitweb: https://git.kernel.org/tip/42e0e95474fc6076b5cd68cab8fa0340a1797a72
Author: Linus Torvalds <torvalds@linux-foundation.org>
AuthorDate: Wed, 28 Aug 2019 10:56:48 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 28 Aug 2019 17:31:31 +02:00
x86/build: Add -Wnoaddress-of-packed-member to REALMODE_CFLAGS, to silence GCC9 build warning
One of the very few warnings I have in the current build comes from
arch/x86/boot/edd.c, where I get the following with a gcc9 build:
arch/x86/boot/edd.c: In function ‘query_edd’:
arch/x86/boot/edd.c:148:11: warning: taking address of packed member of ‘struct boot_params’ may result in an unaligned pointer value [-Waddress-of-packed-member]
148 | mbrptr = boot_params.edd_mbr_sig_buffer;
| ^~~~~~~~~~~
This warning triggers because we throw away all the CFLAGS and then make
a new set for REALMODE_CFLAGS, so the -Wno-address-of-packed-member we
added in the following commit is not present:
6f303d60534c ("gcc-9: silence 'address-of-packed-member' warning")
The simplest solution for now is to adjust the warning for this version
of CFLAGS as well, but it would definitely make sense to examine whether
REALMODE_CFLAGS could be derived from CFLAGS, so that it picks up changes
in the compiler flags environment automatically.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 56e748a..94df086 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -38,6 +38,7 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)
+REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member)
REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
export REALMODE_CFLAGS
^ permalink raw reply related [flat|nested] 2+ messages in thread
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