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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?dVl6cXI3c3A3TlJkM3ZQQ3JSODFCRHU4QjA5NU1GRC9ZczVRcU5QWjZCQUQ1?= =?utf-8?B?VlQ0anNmN29wRmtTUHpFczMxL1d5eE1rL1F4RHo5cndHb0Q3WFJQdDB1VzdU?= =?utf-8?B?dy9mMU0vdnRpR3pwMTZMb2ZMRW51dFJGNlFkMzB5aVRTT01vaFlGa1JPdW5Z?= =?utf-8?B?ZnZ4QmlmUXBqVndOSXF2QlJBL2w2SnNmTkFwdk9SaW56Ymk1M3EwWEFGaWNF?= =?utf-8?B?c0hyaWRGcmtIV1FEaFdWQTFOMWpBNEtrTG1DYTVVaWdMcDlicVVCUjU0V1pU?= =?utf-8?B?ZXdkeXdNekZaQW5oRWNrVDVPMGJMa084ZGEvSHowK2NTcGEwZUhGSG8rWjhE?= =?utf-8?B?akJZSVNYc2wzRC9QWHFSTkQ0L0thbGlXOXE2TDFETU5IektUNURDbWhFdFlZ?= =?utf-8?B?dDR4NFhwSSs0emNEZkRmNnpJRlhyRHVMN1VodmZWSGoydW5ZYmVQdmEyRTlH?= =?utf-8?B?UzNHTkM3ZTNCVEY2MnNWSFNEbGVsTVdMSmYzeU14Tm5RdXhMc3QwcmxjSUJ5?= =?utf-8?B?UkNoQW1VaDJQd1VYbm5MY1ZSeFdTM2xhVWtLTEZGcmtHWWwzMm9xZWNxNC9w?= =?utf-8?B?NVpGYkNlb0Rka0xudTZjMkU4K0c0M09qK0dZNHEzU0RTdFM3TWpRSHZrVjVq?= =?utf-8?B?MER1WVpvSXJSWW0vc2RSWUJxYzJYQWZaZVdwMEhMbDlnYVE2eEZGanh3K1Ny?= =?utf-8?B?WW9VdllBWG00VW0rRHVvblUzWUZleFNCTWhTYVVvbTVQVHVYMEFjaktNd21V?= =?utf-8?B?bGl1a3BlamN2U3lvbHVQSlpDUW0vcHRWbWsrcWk0ZFYyR1ppajFsYitIVElk?= =?utf-8?B?eEYrSm9OdWNWcGRnRlpuK3VVL25tZDJWb0NoNTBNeTc4MStlTUM4TlNBUHZD?= =?utf-8?B?aVE2OG4yZm5pbHpPdHJQMU16czBzSFdVVVR0UFF3YzVPcWVpSCtXOUovVEZ5?= =?utf-8?B?NTVSckhrWjhUQ1c0S0xmRVk4S3RMck5KRHBYU2hkM1NwVFNCV2I3TmtKa0Rx?= =?utf-8?B?bVdiRlE0YWNjNVNTS1A5WjR2dnVXRWJoR283SXdwajc1TFlGWmVHNTdzU3BM?= =?utf-8?B?Z3RKKzNCN3ovcHJsMkNUV3FRZ2hvRDNCbktVK3Q5UTZDMjl6aVorWm1FTzNL?= =?utf-8?B?aU5WRHJyS1FCN1lhbk5pZWlEcy9OSkFUcHg4YlAyQW53ak10WVJEbWgxWkV4?= =?utf-8?B?YnlaeVRNdzdIb2R6NHM4THdJaHU4Q1F5NWE4WUVjb0ZxZzdhN1FSdkRGUElJ?= =?utf-8?B?NTdmNjFaV1JuYlFVZVl2ZllFSXlLQTFReC81ZVVlbjcrN1NXVUtNNmFsUWZn?= =?utf-8?B?bWdXbkIzMmZub3lBckNaQXVuMzRPVUZaSUVxYjNjS29jQjluanB6Q3lkV2dO?= =?utf-8?B?aWVrQm9QN2xDNUhMSW16eEFwTVlINHMvbmp3eFFaTTk4alFRM1dVcXRQZTc2?= =?utf-8?B?Qm1DRis3ZlRQMzhPenF4Q1ZGK2JSMG54L2hzcEViYXVxQ0llNDk0Qk9iay92?= =?utf-8?B?OGNVRkNDMERVTjhJSmtaM2pJQVZWeDVqODlKVmxHVEhteWNWNzI3U25kMWRh?= =?utf-8?B?T1MzS0JLM0NmOGVHRG5oRUd5S3lRSnRTZm1aUlcxSFNFeEFqWTFqWlhnZGJL?= =?utf-8?B?Z0ljUjdVQkl6ZE9mUThUcG9aNjd5aWhZMEZhU2RYUWhBYk93L2dCRW9tR0Vu?= =?utf-8?B?cmV6SWZVT0dyNkwzMHRwdFNianBWMHIveENmR3ovYVY3VDllcnVZR2NuN1Vy?= =?utf-8?Q?gSpPeshSbcA+LMYwT4L4oZIdjmDLzr4q1Gyw+YR?= X-MS-Exchange-CrossTenant-Network-Message-Id: 2b3b4927-f426-4873-f5bc-08d8e4673f89 X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Mar 2021 08:25:37.3637 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: C7u7jA1/iCG+Vq82GTlSqH07hhzM+3vvBY2VmwlMTa0jegvSbXVIH3m+qli4a+h+3mabH/X/C30kyEAMlAFQOA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB5356 X-OriginatorOrg: citrix.com On Thu, Mar 11, 2021 at 09:09:22AM +0100, Jan Beulich wrote: > On 10.03.2021 18:52, Julien Grall wrote: > > On 10/03/2021 16:21, Jan Beulich wrote: > >> On 10.03.2021 15:58, Julien Grall wrote: > >>> On 10/03/2021 10:13, Jan Beulich wrote: > >>> 2) A compiler will not be able to help us if we are adding code > >>> without initialized vaddrs. > >>> > >>> It also feels wrong to me to try to write Xen in a way that will make a > >>> 10 years compiler happy... > >> > >> As said above - we've worked around limitations quite a few times > >> in the past. This is just one more instance. > > > > I find amusing you wrote that when you complained multiple time when > > someone was re-using existing bad pattern. :) > > Well, thing is - I don't view this as a bad pattern. The only question > really is whether NULL is a good initializer here. As per above a non- > canonical pointer may be better, but then we have quite a few places > elsewhere to fix. Sorry for jumping in the middle but I think that would be a very dangerous move for Xen to do. We have been using implicit conversions of pointers to booleans all over the place, assuming that NULL == false, hence NULL no longer mapping to false would break a lot of our code. ie: if ( foo ) free(foo); Would no longer work as expected. Thanks, Roger.