Commit Graph

16 Commits

Author SHA1 Message Date
Michael S. Tsirkin
d757573e69 compiler: expression version of QEMU_BUILD_BUG_ON
QEMU_BUILD_BUG_ON uses a typedef in order to be safe
to use outside functions, but sometimes it's useful
to have a version that can be used within an expression.
Following what Linux does, introduce QEMU_BUILD_BUG_ON_ZERO
that return zero after checking condition at build time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2017-02-01 03:37:17 +02:00
Michael S. Tsirkin
f291887e8e compiler: rework BUG_ON using a struct
There are theoretical concerns that some compilers might not trigger
build failures on attempts to define an array of size (x ? -1 : 1) where
x is a variable and make it a variable sized array instead. Let rewrite
using a struct with a negative bit field size instead as there are no
dynamic bit field sizes.  This is similar to what Linux does.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2017-02-01 03:37:17 +02:00
Michael S. Tsirkin
60abf0a5e0 QEMU_BUILD_BUG_ON: use __COUNTER__
Some headers use QEMU_BUILD_BUG_ON. This causes a problem
if the C file including that header happens to have
QEMU_BUILD_BUG_ON at the same line number.

Fix using a widely available extension: __COUNTER__.
If unavailable, provide a stub.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-02-01 03:37:17 +02:00
Michael S. Tsirkin
f298318284 compiler: drop ; after BUILD_BUG_ON
All users include the trailing ; anyway, let's require that -
it seems cleaner.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2017-01-31 15:57:27 +02:00
Felipe Franciosi
cc9d8a3b2c compiler: Swap 'public domain' header for license
As discussed on the list [1], having a comment stating that this file
is "public domain" is arguably wrong and not legally binding. This patch
replaces that comment with a clear GPLv2+ license as proposed in [2].

[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-09/msg06151.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-09/msg06217.html

Worth noting, compiler.h was originally created on 5c026320 by splitting
qemu-common.h. At the time, qemu-common.h was already GPLv2+.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Message-Id: <1474642971-11866-1-git-send-email-felipe@nutanix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27 11:57:29 +02:00
Paolo Bonzini
8bff06a0bb compiler: never omit assertions if using a static analysis tool
Assertions help both Coverity and the clang static analyzer avoid
false positives, but on the other hand both are confused when
the condition is compiled as (void)(x != FOO).  Always expand
assertion macros when using Coverity or clang, through a new
QEMU_STATIC_ANALYSIS preprocessor symbol.

This fixes a couple false positives in TCG.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-17 09:59:21 +02:00
Emilio G. Cota
911a4d2215 compiler.h: add QEMU_ALIGNED() to enforce struct alignment
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-2-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-06-11 22:59:33 +00:00
Peter Maydell
90ce6e2644 include: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Eric Blake
888ea96aae build: Don't redefine 'inline'
Actively redefining 'inline' is wrong for C++, where gcc has an
extension 'inline namespace' which fails to compile if the
keyword 'inline' is replaced by a macro expansion.  This will
matter once we start to include "qemu/osdep.h" first from C++
files, depending also on whether the system headers are new
enough to be using the gcc extension.

But rather than just guard things by __cplusplus, let's look at
the overall picture.  Commit df2542c737 in 2007 defined 'inline'
to the gcc attribute __always_inline__, with the rationale "To
avoid discarded inlining bug".  But compilers have improved since
then, and we are probably better off trusting the compiler rather
than trying to force its hand.

So just nuke our craziness.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1455043788-28112-1-git-send-email-eblake@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-02-16 12:07:03 +00:00
Peter Maydell
24134c4e91 compiler.h: Use glue() in QEMU_BUILD_BUG_ON define
Rather than rolling custom concatenate-strings macros for the
QEMU_BUILD_BUG_ON macro to use, use the glue() macro we already
have (since it's now available to us in this header).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
2015-08-19 16:29:53 +01:00
Peter Maydell
4912086865 osdep.h: Move some compiler-specific things to compiler.h
osdep.h has a few things which are really compiler specific;
move them to compiler.h, and include compiler.h from osdep.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
2015-08-19 16:29:53 +01:00
Daniel P. Berrange
a31bdae5a7 qom: Add object_new_with_props() / object_new_withpropv() helpers
It is reasonably common to want to create an object, set a
number of properties, register it in the hierarchy and then
mark it as complete (if a user creatable type). This requires
quite a lot of error prone, verbose, boilerplate code to achieve.

First a pair of functions object_set_props() / object_set_propv()
are added which allow for a list of objects to be set in
one single API call.

Then object_new_with_props() / object_new_with_propv() constructors
are added which simplify the sequence of calls to create an
object, populate properties, register in the object composition
tree and mark the object complete, into a single method call.

Usage would be:

   Error *err = NULL;
   Object *obj;
   obj = object_new_with_propv(TYPE_MEMORY_BACKEND_FILE,
                               object_get_objects_root(),
                               "hostmem0",
                               &err,
                               "share", "yes",
                               "mem-path", "/dev/shm/somefile",
                               "prealloc", "yes",
                               "size", "1048576",
                               NULL);

Note all property values are passed in string form and will
be parsed into their required data types, using normal QOM
semantics for parsing from string format.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-06-19 18:42:18 +02:00
Richard Henderson
58099c8066 qemu/compiler: Define QEMU_ARTIFICIAL
The combination of always_inline + artificial allows tiny inline
functions to be written that do not interfere with debugging.
In particular, gdb will not step into an artificial function.

The always_inline attribute was introduced in gcc 4.2,
and the artificial attribute was introduced in gcc 4.3.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-09-29 14:55:28 -04:00
Stefan Weil
87e613ea9e audio: Replace static functions in header file by macros, remove GCC_ATTR
Using macros instead of static functions for dolog and for ldebug
simplifies the code and can also reduce the total code size.

GCC_ATTR was only used in audio_int.h, so it is now unused and
the definition can be removed from compiler.h.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-21 22:52:50 +04:00
Paolo Bonzini
99835e0084 compiler: fix warning with GCC 4.8.0
GCC 4.8.0 introduces a new warning:

    block/qcow2-snapshot.c: In function 'qcow2_write_snapshots’:
    block/qcow2-snapshot.c:252:18: error: typedef 'qemu_build_bug_on__253'
              locally defined but not used [-Werror=unused-local-typedefs]
         QEMU_BUILD_BUG_ON(offsetof(QCowHeader, snapshots_offset) !=
                  ^
    cc1: all warnings being treated as errors

(Caret diagnostics aren't perfect yet with macros... :)) Work around it
with __attribute__((unused)).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1364391272-1128-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-27 10:10:14 -05:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00