diff options
| author | Thomas Huth <thuth@redhat.com> | 2018-11-30 09:23:16 +0100 |
|---|---|---|
| committer | Thomas Huth <thuth@redhat.com> | 2019-01-22 06:26:31 +0100 |
| commit | 798b858130a92f45540e655253b62ddd733ded8c (patch) | |
| tree | 0c9178131ea2d45590a5f88ba6a4cc97227b70a5 | |
| parent | b0b36c021b95eb69451a3e540c9b029a8fb5e21b (diff) | |
linux-user: Fix compilation with clang 3.4
Clang version 3.4.2 does not know the -Wpragmas option yet and bails
out with an error when we try to disable it in linux-user/qemu.h.
Fortunately, clang has a __has_warning() macro which allows us to add
an explicit check for the option that we want to ignore. With that we
can check for the availability of "-Waddress-of-packed-member" properly
and do not need the "-Wpragmas" at all here.
Fixes: 850d5e330a9c68cc998cecc02caf8a3c8d1ee8a3
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
| -rw-r--r-- | include/qemu/compiler.h | 4 | ||||
| -rw-r--r-- | linux-user/qemu.h | 6 |
2 files changed, 5 insertions, 5 deletions
diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h index 2d8f507c73..296b2fd572 100644 --- a/include/qemu/compiler.h +++ b/include/qemu/compiler.h @@ -113,6 +113,10 @@ #define GCC_FMT_ATTR(n, m) #endif +#ifndef __has_warning +#define __has_warning(x) 0 /* compatibility with non-clang compilers */ +#endif + #ifndef __has_feature #define __has_feature(x) 0 /* compatibility with non-clang compilers */ #endif diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 069df8f1f9..ef400cb78a 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -474,17 +474,13 @@ static inline int access_ok(int type, abi_ulong addr, abi_ulong size) * 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__ +#if defined(__clang__) && __has_warning("-Waddress-of-packed-member") #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 \ |