Re: [PULL 0/1] Quick fix patches

[Thomas Huth <thuth@redhat.com>]

On 30/08/2023 15.16, Stefan Hajnoczi wrote:
> Hi,
> The patch introduces the following build failure:
> 
> cc -m64 -mcx16 -Isubprojects/libvhost-user/libvhost-user.a.p
> -Isubprojects/libvhost-user -I../subprojects/libvhost-user
> -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu99 -O2 -g
> -Wsign-compare -Wdeclaration-after-statement -Wstrict-aliasing
> -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing
> -fno-common -fwrapv -fPIE -pthread -D_GNU_SOURCE -MD -MQ
> subprojects/libvhost-user/libvhost-user.a.p/libvhost-user.c.o -MF
> subprojects/libvhost-user/libvhost-user.a.p/libvhost-user.c.o.d -o
> subprojects/libvhost-user/libvhost-user.a.p/libvhost-user.c.o -c
> ../subprojects/libvhost-user/libvhost-user.c
> In file included from ../subprojects/libvhost-user/include/atomic.h:18,
> from ../subprojects/libvhost-user/libvhost-user.c:53:
> ../subprojects/libvhost-user/include/compiler.h:38:40: error: missing
> binary operator before token "("
> 38 | #if defined(__clang__) && __has_warning("-Waddress-of-packed-member")
> | ^
> 
> https://gitlab.com/qemu-project/qemu/-/jobs/4981576093

IIRC older versions of GCC do not have __has_warning() yet, so if you want 
to use this in compiler.h, you have to do it below the line in compiler.h 
that adds this:

#ifndef __has_warning
#define __has_warning(x) 0 /* compatibility with non-clang compilers */
#endif

  HTH,
   Thomas