On 15/03/2021 16.37, Peter Maydell wrote:
On Mon, 15 Mar 2021 at 15:26, Thomas Huth <[email protected]> wrote:
On 15/03/2021 15.52, Philippe Mathieu-Daudé wrote:
On 3/15/21 2:54 PM, Thomas Huth wrote:
We are generating a lot of target-specific defines in the *-config-devices.h
and *-config-target.h files. Using them in common code is wrong and leads
to very subtle bugs since a "#ifdef CONFIG_SOMETHING" is not working there
as expected. To avoid these issues, we are already poisoning some of the
macros in include/exec/poison.h - but maintaining this list manually is
cumbersome. Thus let's generate the list of poisoned macros automatically
instead.
Note that CONFIG_TCG (which is also defined in config-host.h) and
IIRC we can't poison CONFIG_XEN / CONFIG_HAX because they are
pulled in via "sysemu/hw_accel.h".
That's a good hint ... but I think it can be fixed with a patch like this:
diff a/include/sysemu/hw_accel.h b/include/sysemu/hw_accel.h
--- a/include/sysemu/hw_accel.h
+++ b/include/sysemu/hw_accel.h
@@ -12,19 +12,24 @@
#define QEMU_HW_ACCEL_H
#include "hw/core/cpu.h"
+
+#ifdef NEED_CPU_H
+
#include "sysemu/hax.h"
#include "sysemu/kvm.h"
#include "sysemu/hvf.h"
#include "sysemu/whpx.h"
This doesn't look right, because sysemu/kvm.h itself contains
a NEED_CPU_H check, which implies that there are situations where
NEED_CPU_H is not defined and we need to pull in the header.
I just tried, and QEMU seems to compile fine with my patch... I guess the
check for NEED_CPU_H is mainly required for files that include
"sysemu/kvm.h" directly, without the detour via hw_accel.h.
Anyway, I can also push the check rather into the hax.h, hvf.h and whpx.h
files themselves, to make them more similar to kvm.h.
Thomas
