osdep: set _FORTIFY_SOURCE=2 when optimization is enabled
Currently we set _FORTIFY_SOURCE=2 as a compiler argument when the
meson 'optimization' setting is non-zero, the compiler is GCC and
the target is Linux.
While the default QEMU optimization level is 2, user could override
this by setting CFLAGS="-O0" or --extra-cflags="-O0" when running
configure and this won't be reflected in the meson 'optimization'
setting. As a result we try to enable _FORTIFY_SOURCE=2 and then the
user gets compile errors as it only works with optimization.
Rather than trying to improve detection in meson, it is simpler to
just check the __OPTIMIZE__ define from osdep.h.
The comment about being incompatible with clang appears to be
outdated, as compilation works fine without excluding clang.
In the coroutine code we must set _FORTIFY_SOURCE=0 to stop the
logic in osdep.h then enabling it.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id:
20231003091549.223020-1-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>