From: Kyle Evans <kev...@freebsd.org> Implement PRAGMA_DISABLE_PACKED_WARNING and PRAGMA_REENABLE_PACKED_WARNING macros in bsd-user/qemu.h.
Signed-off-by: Kyle Evans <kev...@freebsd.org> Signed-off-by: Karim Taha <kariem.taha...@gmail.com> --- bsd-user/qemu.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h index edf9602f9b..dfdfa8dd67 100644 --- a/bsd-user/qemu.h +++ b/bsd-user/qemu.h @@ -276,6 +276,37 @@ static inline bool access_ok(int type, abi_ulong addr, abi_ulong size) * These are usually used to access struct data members once the struct has been * locked - usually with lock_user_struct(). */ + +/* + * Tricky points: + * - Use __builtin_choose_expr to avoid type promotion from ?:, + * - Invalid sizes result in a compile time error stemming from + * the fact that abort has no parameters. + * - It's easier to use the endian-specific unaligned load/store + * functions than host-endian unaligned load/store plus tswapN. + * - The pragmas are necessary only to silence a clang false-positive + * warning: see https://bugs.llvm.org/show_bug.cgi?id=39113 . + * - We have to disable -Wpragmas warnings to avoid a complaint about + * an unknown warning type from older compilers that don't know about + * -Waddress-of-packed-member. + * - gcc has bugs in its _Pragma() support in some versions, eg + * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83256 -- so we only + * include the warning-suppression pragmas for clang + */ +#ifdef __clang__ +#define PRAGMA_DISABLE_PACKED_WARNING \ + _Pragma("GCC diagnostic push"); \ + _Pragma("GCC diagnostic ignored \"-Wpragmas\""); \ + _Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"") + +#define PRAGMA_REENABLE_PACKED_WARNING \ + _Pragma("GCC diagnostic pop") + +#else +#define PRAGMA_DISABLE_PACKED_WARNING +#define PRAGMA_REENABLE_PACKED_WARNING +#endif + #define __put_user(x, hptr)\ ({\ int size = sizeof(*hptr);\ -- 2.40.0
