Re: [PATCH for-6.0? 2/6] osdep: protect qemu/osdep.h with extern "C"

[Richard Henderson <richard.henderson@linaro.org>]

On 4/16/21 6:55 AM, Peter Maydell wrote:
> From: Paolo Bonzini<pbonzini@redhat.com>
> 
> System headers may include templates if compiled with a C++ compiler,
> which cause the compiler to complain if qemu/osdep.h is included
> within a C++ source file's 'extern "C"' block.  Add
> an 'extern "C"' block directly to qemu/osdep.h, so that
> system headers can be kept out of it.
> 
> There is a stray declaration early in qemu/osdep.h, which needs
> to be special cased.  Add a definition in qemu/compiler.h to
> make it look nice.
> 
> config-host.h, CONFIG_TARGET, exec/poison.h and qemu/compiler.h
> are included outside the 'extern "C"' block; that is not
> an issue because they consist entirely of preprocessor directives.
> 
> This allows us to move the include of osdep.h in our two C++
> source files outside the extern "C" block they were previously
> using for it, which in turn means that they compile successfully
> against newer versions of glib which insist that glib.h is
> *not*  inside an extern "C" block.
> 
> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> Reviewed-by: Daniel P. Berrangé<berrange@redhat.com>
> [PMM: Moved disas/arm-a64.cc osdep.h include out of its extern "C" block;
>   explained in commit message why we're doing this]
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---
>   include/qemu/compiler.h |  6 ++++++
>   include/qemu/osdep.h    | 10 +++++++++-
>   disas/arm-a64.cc        |  2 +-
>   disas/nanomips.cpp      |  2 +-
>   4 files changed, 17 insertions(+), 3 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~