[PATCH 2/2] Compiler Attributes: naked can be shared

From: Miguel Ojeda
Date: Thu Sep 13 2018 - 20:01:04 EST


The naked attribute is supported by at least gcc >= 4.6 (for ARM,
which is the only current user), gcc >= 8 (for x86), clang >= 3.1
and icc >= 13. See https://godbolt.org/z/350Dyc

Therefore, move it out of compiler-gcc.h so that the definition
is shared by all compilers.

This also fixes Clang support for ARM32 --- 815f0ddb346c
("include/linux/compiler*.h: make compiler-*.h mutually exclusive").

Cc: Stefan Agner <stefan@xxxxxxxx>
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: 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
Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
Reviewed-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 | 8 --------
include/linux/compiler_types.h | 8 ++++++++
2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 25d3dd6b2702..4d36b27214fd 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -79,14 +79,6 @@
#define __noretpoline __attribute__((indirect_branch("keep")))
#endif

-/*
- * it doesn't make sense on ARM (currently the only user of __naked)
- * to trace naked functions because then mcount is called without
- * stack and frame pointer being set up and there is no chance to
- * restore the lr register to the value before mcount was called.
- */
-#define __naked __attribute__((naked)) notrace
-
#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)

#define __optimize(level) __attribute__((__optimize__(level)))
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 3525c179698c..db192becfec4 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -226,6 +226,14 @@ struct ftrace_likely_data {
#define notrace __attribute__((no_instrument_function))
#endif

+/*
+ * it doesn't make sense on ARM (currently the only user of __naked)
+ * to trace naked functions because then mcount is called without
+ * stack and frame pointer being set up and there is no chance to
+ * restore the lr register to the value before mcount was called.
+ */
+#define __naked __attribute__((naked)) notrace
+
#define __compiler_offsetof(a, b) __builtin_offsetof(a, b)

/*
--
2.17.1