summaryrefslogtreecommitdiff
path: root/include/linux/compiler-gcc.h
diff options
context:
space:
mode:
authorJoe Perches <joe@perches.com>2018-08-20 23:15:26 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-21 00:12:38 +0300
commitcafa0010cd51fb711fdcb50fc55f394c5f167a0a (patch)
tree59035cd5f8e7ea85abdd5ce278e820257f4a0663 /include/linux/compiler-gcc.h
parentcc26ebbebde8548014d9329ac2f6cf0178181789 (diff)
downloadlinux-cafa0010cd51fb711fdcb50fc55f394c5f167a0a.tar.xz
Raise the minimum required gcc version to 4.6
Various architectures fail to build properly with older versions of the gcc compiler. An example from Guenter Roeck in thread [1]: > > In file included from ./include/linux/mm.h:17:0, > from ./include/linux/pid_namespace.h:7, > from ./include/linux/ptrace.h:10, > from arch/openrisc/kernel/asm-offsets.c:32: > ./include/linux/mm_types.h:497:16: error: flexible array member in otherwise empty struct > > This is just an example with gcc 4.5.1 for or32. I have seen the problem > with gcc 4.4 (for unicore32) as well. So update the minimum required version of gcc to 4.6. [1] https://lore.kernel.org/lkml/20180814170904.GA12768@roeck-us.net/ Miscellanea: - Update Documentation/process/changes.rst - Remove and consolidate version test blocks in compiler-gcc.h for versions lower than 4.6 Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/compiler-gcc.h')
-rw-r--r--include/linux/compiler-gcc.h86
1 files changed, 18 insertions, 68 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 3e70b7d4e9ed..250b9b7cfd60 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -10,6 +10,10 @@
+ __GNUC_MINOR__ * 100 \
+ __GNUC_PATCHLEVEL__)
+#if GCC_VERSION < 40600
+# error Sorry, your compiler is too old - please upgrade it.
+#endif
+
/* Optimization barrier */
/* The "volatile" is due to gcc bugs */
@@ -58,6 +62,12 @@
#define OPTIMIZER_HIDE_VAR(var) \
__asm__ ("" : "=r" (var) : "0" (var))
+/*
+ * A trick to suppress uninitialized variable warning without generating any
+ * code
+ */
+#define uninitialized_var(x) x = x
+
#ifdef __CHECKER__
#define __must_be_array(a) 0
#else
@@ -91,7 +101,7 @@
* A lot of inline functions can cause havoc with function tracing.
*/
#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \
- !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4)
+ !defined(CONFIG_OPTIMIZE_INLINING)
#define inline \
inline __attribute__((always_inline, unused)) notrace __gnu_inline
#else
@@ -147,47 +157,13 @@
#define __always_unused __attribute__((unused))
#define __mode(x) __attribute__((mode(x)))
-/* gcc version specific checks */
-
-#if GCC_VERSION < 30200
-# error Sorry, your compiler is too old - please upgrade it.
-#endif
-
-#if GCC_VERSION < 30300
-# define __used __attribute__((__unused__))
-#else
-# define __used __attribute__((__used__))
-#endif
-
-#ifdef CONFIG_GCOV_KERNEL
-# if GCC_VERSION < 30400
-# error "GCOV profiling support for gcc versions below 3.4 not included"
-# endif /* __GNUC_MINOR__ */
-#endif /* CONFIG_GCOV_KERNEL */
-
-#if GCC_VERSION >= 30400
#define __must_check __attribute__((warn_unused_result))
#define __malloc __attribute__((__malloc__))
-#endif
-
-#if GCC_VERSION >= 40000
-
-/* GCC 4.1.[01] miscompiles __weak */
-#ifdef __KERNEL__
-# if GCC_VERSION >= 40100 && GCC_VERSION <= 40101
-# error Your version of gcc miscompiles the __weak directive
-# endif
-#endif
#define __used __attribute__((__used__))
#define __compiler_offsetof(a, b) \
__builtin_offsetof(a, b)
-#if GCC_VERSION >= 40100
-# define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
-#endif
-
-#if GCC_VERSION >= 40300
/* Mark functions as cold. gcc will assume any path leading to a call
* to them will be unlikely. This means a lot of manual unlikely()s
* are unnecessary now for any paths leading to the usual suspects
@@ -206,24 +182,19 @@
#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
-#ifndef __CHECKER__
-# define __compiletime_warning(message) __attribute__((warning(message)))
-# define __compiletime_error(message) __attribute__((error(message)))
-#endif /* __CHECKER__ */
-#endif /* GCC_VERSION >= 40300 */
-
-#if GCC_VERSION >= 40400
#define __optimize(level) __attribute__((__optimize__(level)))
#define __nostackprotector __optimize("no-stack-protector")
-#endif /* GCC_VERSION >= 40400 */
-#if GCC_VERSION >= 40500
+#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
#define __latent_entropy __attribute__((latent_entropy))
#endif
-#endif
+#endif /* __CHECKER__ */
/*
* calling noreturn functions, __builtin_unreachable() and __builtin_trap()
@@ -261,10 +232,6 @@
#define randomized_struct_fields_end } __randomize_layout;
#endif
-#endif /* GCC_VERSION >= 40500 */
-
-#if GCC_VERSION >= 40600
-
/*
* When used with Link Time Optimization, gcc can optimize away C functions or
* variables which are referenced only from assembly code. __visible tells the
@@ -273,8 +240,7 @@
*/
#define __visible __attribute__((externally_visible))
-#endif /* GCC_VERSION >= 40600 */
-
+/* gcc version specific checks */
#if GCC_VERSION >= 40900 && !defined(__CHECKER__)
/*
@@ -308,10 +274,8 @@
* folding in __builtin_bswap*() (yet), so don't set these for it.
*/
#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) && !defined(__CHECKER__)
-#if GCC_VERSION >= 40400
#define __HAVE_BUILTIN_BSWAP32__
#define __HAVE_BUILTIN_BSWAP64__
-#endif
#if GCC_VERSION >= 40800
#define __HAVE_BUILTIN_BSWAP16__
#endif
@@ -340,10 +304,9 @@
* https://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html
*/
#define __designated_init __attribute__((designated_init))
+#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
#endif
-#endif /* gcc version >= 40000 specific checks */
-
#if !defined(__noclone)
#define __noclone /* not needed */
#endif
@@ -353,16 +316,6 @@
#endif
/*
- * A trick to suppress uninitialized variable warning without generating any
- * code
- */
-#define uninitialized_var(x) x = x
-
-#if GCC_VERSION >= 50100
-#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
-#endif
-
-/*
* Turn individual warnings and errors on and off locally, depending
* on version.
*/
@@ -374,12 +327,9 @@
#define __diag_GCC_warn warning
#define __diag_GCC_error error
-/* Compilers before gcc-4.6 do not understand "#pragma GCC diagnostic push" */
-#if GCC_VERSION >= 40600
#define __diag_str1(s) #s
#define __diag_str(s) __diag_str1(s)
#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
-#endif
#if GCC_VERSION >= 80000
#define __diag_GCC_8(s) __diag(s)