Re: [PATCH v2] linux-user: Move PRAGMA_DISABLE_PACKED_WARNING to compiler.h

[Warner Losh]

CC Peter Maywell

CC Stefan Hajnoczi

On Tue, Aug 29, 2023 at 12:51 PM Warner Losh <imp@bsdimp.com> wrote:

Replace the slightly older version of this in include/qemu/compiler.h
that was commit as part of bsd-user changes with the newer one from
linux-user. bsd-user has no regreassions with this.

Signed-off-by: Warner Losh <imp@bsdimp.com>
---
 include/qemu/compiler.h  |  6 +-----
 linux-user/qemu.h        | 26 --------------------------
 tests/lcitool/libvirt-ci |  2 +-
 3 files changed, 2 insertions(+), 32 deletions(-)

diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h
index b0374425180..0df9febbe2f 100644
--- a/include/qemu/compiler.h
+++ b/include/qemu/compiler.h
@@ -31,17 +31,13 @@
  *   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          \
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index 4f8b55e2fb0..12821e54d0a 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -193,32 +193,6 @@ static inline bool access_ok(CPUState *cpu, int type,
    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 .
- * - 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
- */
-#if defined(__clang__) && __has_warning("-Waddress-of-packed-member")
-#define PRAGMA_DISABLE_PACKED_WARNING                                   \
-    _Pragma("GCC diagnostic push");                                     \
-    _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_e(x, hptr, e)                                            \
     do {                                                                    \
         PRAGMA_DISABLE_PACKED_WARNING;                                      \
diff --git a/tests/lcitool/libvirt-ci b/tests/lcitool/libvirt-ci
index bbd55b4d18c..9bff3b763b5 160000
--- a/tests/lcitool/libvirt-ci
+++ b/tests/lcitool/libvirt-ci
@@ -1 +1 @@
-Subproject commit bbd55b4d18cce8f89b5167675e434a6941315634
+Subproject commit 9bff3b763b5531a1490e238bfbf77306dc3a6dbb
--
2.41.0