Re: [PATCH] Fix sparse checks processing
On Tue, May 16, 2023 at 06:18:56AM +, Christophe Leroy wrote:
>
>
> Le 15/05/2023 à 23:12, Tom Rini a écrit :
> > On Fri, May 05, 2023 at 10:39:39AM +0200, Christophe Leroy wrote:
> >
> >> A lot of errors are encountered when building with sparse checking
> >> activated (make C=1 or make C=2).
> >>
> >> Many of them are fixed in Linux.
> >>
> >> Resynchronise Makefile and include/linux/build_bug.h with Linux
> >> kernel sources by porting the following Linux commits into u-boot:
> >> - 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
> >> - 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
> >> - 8788994376d8 ("linux/build_bug.h: change type to int")
> >> - 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for
> >> Sparse")
> >> - c60d3b79423a ("build_bug.h: remove negative-array fallback for
> >> BUILD_BUG_ON()")
> >> - 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")
> >>
> >> Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
> >> 'warning: preprocessor token offsetof redefined'") because the
> >> error it creates is worse than the warning it is trying to fix.
> >>
> >> Signed-off-by: Christophe Leroy
> >
> > First, I've applied to u-boot/next now. But second, I had mentioned CI
> > testing too, but seeing the level of checker-error output on qemu-arm I
> > am reluctant to add a test that should build-to-completion but error so
> > much as I worry about it being seen as a low quality test.
> >
>
> Well, at least we can now start detecting and fixing them.
>
> Also, I don't know how feasible it is, but in Linux kernel the robots
> report new warnings/error only so that you know you are not adding new
> ones with new commits. Could CI do that too ?
In theory something like those could be adapted, and if you can either
test something for GitLab / Azure, or even something I can integrate in
to my release scripts like Coverity scan for after the fact new
introductions, I'd appreciate it.
--
Tom
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Re: [PATCH] Fix sparse checks processing
Le 15/05/2023 à 23:12, Tom Rini a écrit :
> On Fri, May 05, 2023 at 10:39:39AM +0200, Christophe Leroy wrote:
>
>> A lot of errors are encountered when building with sparse checking
>> activated (make C=1 or make C=2).
>>
>> Many of them are fixed in Linux.
>>
>> Resynchronise Makefile and include/linux/build_bug.h with Linux
>> kernel sources by porting the following Linux commits into u-boot:
>> - 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
>> - 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
>> - 8788994376d8 ("linux/build_bug.h: change type to int")
>> - 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for
>> Sparse")
>> - c60d3b79423a ("build_bug.h: remove negative-array fallback for
>> BUILD_BUG_ON()")
>> - 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")
>>
>> Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
>> 'warning: preprocessor token offsetof redefined'") because the
>> error it creates is worse than the warning it is trying to fix.
>>
>> Signed-off-by: Christophe Leroy
>
> First, I've applied to u-boot/next now. But second, I had mentioned CI
> testing too, but seeing the level of checker-error output on qemu-arm I
> am reluctant to add a test that should build-to-completion but error so
> much as I worry about it being seen as a low quality test.
>
Well, at least we can now start detecting and fixing them.
Also, I don't know how feasible it is, but in Linux kernel the robots
report new warnings/error only so that you know you are not adding new
ones with new commits. Could CI do that too ?
Christophe
Re: [PATCH] Fix sparse checks processing
On Fri, May 05, 2023 at 10:39:39AM +0200, Christophe Leroy wrote:
> A lot of errors are encountered when building with sparse checking
> activated (make C=1 or make C=2).
>
> Many of them are fixed in Linux.
>
> Resynchronise Makefile and include/linux/build_bug.h with Linux
> kernel sources by porting the following Linux commits into u-boot:
> - 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
> - 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
> - 8788994376d8 ("linux/build_bug.h: change type to int")
> - 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for
> Sparse")
> - c60d3b79423a ("build_bug.h: remove negative-array fallback for
> BUILD_BUG_ON()")
> - 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")
>
> Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
> 'warning: preprocessor token offsetof redefined'") because the
> error it creates is worse than the warning it is trying to fix.
>
> Signed-off-by: Christophe Leroy
First, I've applied to u-boot/next now. But second, I had mentioned CI
testing too, but seeing the level of checker-error output on qemu-arm I
am reluctant to add a test that should build-to-completion but error so
much as I worry about it being seen as a low quality test.
--
Tom
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Description: PGP signature
[PATCH] Fix sparse checks processing
A lot of errors are encountered when building with sparse checking
activated (make C=1 or make C=2).
Many of them are fixed in Linux.
Resynchronise Makefile and include/linux/build_bug.h with Linux
kernel sources by porting the following Linux commits into u-boot:
- 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
- 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
- 8788994376d8 ("linux/build_bug.h: change type to int")
- 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for
Sparse")
- c60d3b79423a ("build_bug.h: remove negative-array fallback for
BUILD_BUG_ON()")
- 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")
Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
'warning: preprocessor token offsetof redefined'") because the
error it creates is worse than the warning it is trying to fix.
Signed-off-by: Christophe Leroy
---
Makefile | 6 +-
include/linux/build_bug.h | 40 ---
include/linux/stddef.h| 8 +---
3 files changed, 14 insertions(+), 40 deletions(-)
diff --git a/Makefile b/Makefile
index 4f4f014d2c..6bf62ebad6 100644
--- a/Makefile
+++ b/Makefile
@@ -423,7 +423,8 @@ DTC_MIN_VERSION := 010406
CHECK = sparse
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
- -Wbitwise -Wno-return-void -D__CHECK_ENDIAN__ $(CF)
+ -Wbitwise -Wno-return-void -Wno-unknown-attribute \
+ -D__CHECK_ENDIAN__ $(CF)
KBUILD_CPPFLAGS := -D__KERNEL__ -D__UBOOT__
@@ -1032,6 +1033,9 @@ ifeq
($(CONFIG_ARC)$(CONFIG_NIOS2)$(CONFIG_X86)$(CONFIG_XTENSA),)
LDFLAGS_u-boot += -Ttext $(CONFIG_TEXT_BASE)
endif
+# make the checker run with the right architecture
+CHECKFLAGS += --arch=$(ARCH)
+
# insure the checker run with the right endianness
CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
diff --git a/include/linux/build_bug.h b/include/linux/build_bug.h
index 9c7088bafa..20c2dc7f4b 100644
--- a/include/linux/build_bug.h
+++ b/include/linux/build_bug.h
@@ -4,15 +4,16 @@
#include
#ifdef __CHECKER__
-#define __BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
-#define BUILD_BUG_ON_NOT_POWER_OF_2(n) (0)
#define BUILD_BUG_ON_ZERO(e) (0)
-#define BUILD_BUG_ON_NULL(e) ((void *)0)
-#define BUILD_BUG_ON_INVALID(e) (0)
-#define BUILD_BUG_ON_MSG(cond, msg) (0)
-#define BUILD_BUG_ON(condition) (0)
-#define BUILD_BUG() (0)
#else /* __CHECKER__ */
+/*
+ * Force a compilation error if condition is true, but also produce a
+ * result (of value 0 and type int), so the expression can be used
+ * e.g. in a structure initializer (or where-ever else comma expressions
+ * aren't permitted).
+ */
+#define BUILD_BUG_ON_ZERO(e) ((int)sizeof(struct { int:(-!!(e)); }))
+#endif /* __CHECKER__ */
/* Force a compilation error if a constant expression is not a power of 2 */
#define __BUILD_BUG_ON_NOT_POWER_OF_2(n) \
@@ -20,15 +21,6 @@
#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
-/*
- * Force a compilation error if condition is true, but also produce a
- * result (of value 0 and type size_t), so the expression can be used
- * e.g. in a structure initializer (or where-ever else comma expressions
- * aren't permitted).
- */
-#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:(-!!(e)); }))
-#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:(-!!(e)); }))
-
/*
* BUILD_BUG_ON_INVALID() permits the compiler to check the validity of the
* expression but avoids the generation of any code, even if that expression
@@ -52,23 +44,9 @@
* If you have some code which relies on certain constants being equal, or
* some other compile-time-evaluated condition, you should use BUILD_BUG_ON to
* detect if someone changes it.
- *
- * The implementation uses gcc's reluctance to create a negative array, but gcc
- * (as of 4.4) only emits that error for obvious cases (e.g. not arguments to
- * inline functions). Luckily, in 4.3 they added the "error" function
- * attribute just for this type of case. Thus, we use a negative sized array
- * (should always create an error on gcc versions older than 4.4) and then call
- * an undefined function with the error attribute (should always create an
- * error on gcc 4.3 and later). If for some reason, neither creates a
- * compile-time error, we'll still have a link-time error, which is harder to
- * track down.
*/
-#ifndef __OPTIMIZE__
-#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
-#else
#define BUILD_BUG_ON(condition) \
BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
-#endif
/**
* BUILD_BUG - break compile if used.
@@ -98,6 +76,4 @@
#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
#define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
-#endif /* __CHECKER__ */
-
#endif /* _LINUX_
