Hi, There will always be a need to deprecate things. Here I'm tackling the QOM (class) properties, since they can be set from some CLI options (-object -device -global ...).
As an experiment, we add object_class_property_deprecate() to register a class property as deprecated (since some version), then we deprecate the TYPE_PFLASH_CFI02 'width' property, and finally as a bonus we emit a warning when the deprecation period is over, as a reminder. (For that we introduce few 'versions' helpers). Output example: $ qemu-system-arm -M musicpal,accel=qtest -S \ -drive if=pflash,driver=null-co,read-zeroes=on,size=8M \ -global driver=cfi.pflash02,property=width,value=2 qemu-system-arm: warning: Property 'cfi.pflash02.width' is deprecated (renamed as 'cfi.pflash02.device-width'). $ qemu-system-arm -M musicpal,accel=qtest -S \ -drive if=pflash,driver=null-co,read-zeroes=on,size=8M \ -global driver=cfi.pflash02,property=device-width,value=2 qemu-system-arm: warning: Property 'cfi.pflash02.width' has been deprecated in release v8.0 and can be removed. Thought? Regards, Phil. [earlier inspiration: https://lore.kernel.org/qemu-devel/Y7wlnqwU+/aue...@redhat.com/] Philippe Mathieu-Daudé (4): qom: Introduce object_class_property_deprecate() hw/block: Rename TYPE_PFLASH_CFI02 'width' property as 'device-width' util: Introduce helpers to compare QEMU versions qom: Warn when deprecated class property can be removed hw/block/pflash_cfi02.c | 8 +++++++- include/qemu/qemu-version.h | 36 ++++++++++++++++++++++++++++++++++++ include/qom/object.h | 17 +++++++++++++++++ qom/object.c | 30 ++++++++++++++++++++++++++++++ util/meson.build | 1 + util/qemu-version.c | 37 +++++++++++++++++++++++++++++++++++++ 6 files changed, 128 insertions(+), 1 deletion(-) create mode 100644 include/qemu/qemu-version.h create mode 100644 util/qemu-version.c -- 2.38.1
