Merge tag 'compiler-attributes-for-linus-v5.0-rc7' of git://github.com/ojeda/linux
Pull compiler attributes fixes from Miguel Ojeda:
"Clean the new GCC 9 -Wmissing-attributes warnings
The upcoming GCC 9 release extends the -Wmissing-attributes warnings
(enabled by -Wall) to C and aliases: it warns when particular function
attributes are missing in the aliases but not in their target, e.g.:
void __cold f(void) {}
void __alias("f") g(void);
diagnoses:
warning: 'g' specifies less restrictive attribute than
its target 'f': 'cold' [-Wmissing-attributes]
These patch series clean these new warnings. Most of them are caused
by the module_init/exit macros"
Link: https://lore.kernel.org/lkml/20190125104353.2791-1-labbott@redhat.com/
* tag 'compiler-attributes-for-linus-v5.0-rc7' of git://github.com/ojeda/linux:
include/linux/module.h: copy __init/__exit attrs to init/cleanup_module
Compiler Attributes: add support for __copy (gcc >= 9)
lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure
diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h
index 19f32b0..6b318ef 100644
--- a/include/linux/compiler_attributes.h
+++ b/include/linux/compiler_attributes.h
@@ -34,6 +34,7 @@
#ifndef __has_attribute
# define __has_attribute(x) __GCC4_has_attribute_##x
# define __GCC4_has_attribute___assume_aligned__ (__GNUC_MINOR__ >= 9)
+# define __GCC4_has_attribute___copy__ 0
# define __GCC4_has_attribute___designated_init__ 0
# define __GCC4_has_attribute___externally_visible__ 1
# define __GCC4_has_attribute___noclone__ 1
@@ -101,6 +102,19 @@
#define __attribute_const__ __attribute__((__const__))
/*
+ * Optional: only supported since gcc >= 9
+ * Optional: not supported by clang
+ * Optional: not supported by icc
+ *
+ * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-copy-function-attribute
+ */
+#if __has_attribute(__copy__)
+# define __copy(symbol) __attribute__((__copy__(symbol)))
+#else
+# define __copy(symbol)
+#endif
+
+/*
* Don't. Just don't. See commit 771c035372a0 ("deprecate the '__deprecated'
* attribute warnings entirely and for good") for more information.
*
diff --git a/include/linux/module.h b/include/linux/module.h
index 8fa38d3..f5bc4c0 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -129,13 +129,13 @@ extern void cleanup_module(void);
#define module_init(initfn) \
static inline initcall_t __maybe_unused __inittest(void) \
{ return initfn; } \
- int init_module(void) __attribute__((alias(#initfn)));
+ int init_module(void) __copy(initfn) __attribute__((alias(#initfn)));
/* This is only required if you want to be unloadable. */
#define module_exit(exitfn) \
static inline exitcall_t __maybe_unused __exittest(void) \
{ return exitfn; } \
- void cleanup_module(void) __attribute__((alias(#exitfn)));
+ void cleanup_module(void) __copy(exitfn) __attribute__((alias(#exitfn)));
#endif
diff --git a/lib/crc32.c b/lib/crc32.c
index 45b1d67..4a20455d 100644
--- a/lib/crc32.c
+++ b/lib/crc32.c
@@ -206,8 +206,8 @@ u32 __pure __weak __crc32c_le(u32 crc, unsigned char const *p, size_t len)
EXPORT_SYMBOL(crc32_le);
EXPORT_SYMBOL(__crc32c_le);
-u32 crc32_le_base(u32, unsigned char const *, size_t) __alias(crc32_le);
-u32 __crc32c_le_base(u32, unsigned char const *, size_t) __alias(__crc32c_le);
+u32 __pure crc32_le_base(u32, unsigned char const *, size_t) __alias(crc32_le);
+u32 __pure __crc32c_le_base(u32, unsigned char const *, size_t) __alias(__crc32c_le);
/*
* This multiplies the polynomials x and y modulo the given modulus.
