[PATCH v4 07/13] Compiler Attributes: remove unneeded sparse (__CHECKER__) tests

From: Miguel Ojeda
Date: Sat Sep 08 2018 - 17:26:01 EST


Sparse knows about a few more attributes now, so we can remove
the __CHECKER__ conditions from them (which, in turn, allow us
to move some of them later on to compiler_attributes.h).

* assume_aligned: since sparse's commit ffc860b ("sparse:
ignore __assume_aligned__ attribute"), included in 0.5.1

* error: since sparse's commit 0a04210 ("sparse: Add 'error'
to ignored attributes"), included in 0.5.0

* hotpatch: since sparse's commit 6043210 ("sparse/parse.c:
ignore hotpatch attribute"), included in 0.5.1

* warning: since sparse's commit 977365d ("Avoid "attribute
'warning': unknown attribute" warning"), included in 0.4.2

On top of that, __must_be_array does not need it either because:

* Even ancient versions of sparse do not have a problem

* BUILD_BUG_ON_ZERO() is currently disabled for __CHECKER__

Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Eli Friedman <efriedma@xxxxxxxxxxxxxx>
Cc: Christopher Li <sparse@xxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Joe Perches <joe@xxxxxxxxxxx>
Cc: Dominique Martinet <asmadeus@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-sparse@xxxxxxxxxxxxxxx
Acked-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx>
---
include/linux/compiler-gcc.h | 6 ++----
include/linux/compiler.h | 4 ----
include/linux/compiler_types.h | 2 +-
3 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 3b32bbfa5a49..1ca6a51cfaa9 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -76,14 +76,12 @@

#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)

-#ifndef __CHECKER__
#define __compiletime_warning(message) __attribute__((__warning__(message)))
#define __compiletime_error(message) __attribute__((__error__(message)))

-#ifdef LATENT_ENTROPY_PLUGIN
+#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
#define __latent_entropy __attribute__((latent_entropy))
#endif
-#endif /* __CHECKER__ */

/*
* calling noreturn functions, __builtin_unreachable() and __builtin_trap()
@@ -131,7 +129,7 @@

/* gcc version specific checks */

-#if GCC_VERSION >= 40900 && !defined(__CHECKER__)
+#if GCC_VERSION >= 40900
/*
* __assume_aligned(n, k): Tell the optimizer that the returned
* pointer can be assumed to be k modulo n. The second argument is
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 165b1d5683ed..4030a2940d6b 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -357,11 +357,7 @@ static inline void *offset_to_ptr(const int *off)
compiletime_assert(__native_word(t), \
"Need native word sized stores/loads for atomicity.")

-#ifdef __CHECKER__
-#define __must_be_array(a) 0
-#else
/* &a[0] degrades to a pointer: a different type from an array */
#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
-#endif

#endif /* __LINUX_COMPILER_H */
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 5ff9cda893f4..a3eceb3ad1b3 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -218,7 +218,7 @@ struct ftrace_likely_data {
#define __must_check
#endif

-#if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__)
+#if defined(CC_USING_HOTPATCH)
#define notrace __attribute__((hotpatch(0, 0)))
#else
#define notrace __attribute__((__no_instrument_function__))
--
2.17.1