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X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?QzRScFRsOUlXU08wRWdITkx6QWxqS1NiRm9FZnNiTnBsSjF4U2V6U0ZPQW1w?= =?utf-8?B?d0ZGWGE5aWI1ZExtTGU5TmN3cXpzcStyb2lwSGRJLzhSeTB1RHB4dEY2b3E4?= =?utf-8?B?b0pZRlQ0YUhwYjJNdXpFMHpjQkovV3gzV2JqdXhHRHBOcXBzVmZXM2RublVK?= =?utf-8?B?WHBPS3BSeVp0UFZJNWVnMUkyUUVxRlMyWXVXRDZyZUszZDJUbE1UcWFER0tQ?= =?utf-8?B?aXZHQno2MTB0SWNFcnBKanl3S2g3ME1wbTU3eWZKN2x6RGs4MlYzTXovUmpx?= =?utf-8?B?K3Vma1J1c0w3Z0V2SmlNVGQyam1zQ25EWHRvZlJ6aURZazZVLzM1T1QyTlZH?= =?utf-8?B?b3JrcW1DOW4xZXFkalVGSWl3Q2pUUmRvb3Z5eWdmQ1VrZ2p5cEJmeDlHSE1P?= =?utf-8?B?Nk1FZUhTZ2NkSUxtV240V2RLMVdzYTZOMEpZY3VzNnVVK1dpQ3Fia3hlUmR5?= =?utf-8?B?cXJBa1J2NzlOU2xsRDlKK1NTYzA0MnFjN2ljU3FxTWE2Vk1BdHZnQ2NpbDZG?= =?utf-8?B?cTVrNldnZkQ3U1U5SGtwZ2ZaWVZHUWZtWDNGYzBDejFtazNKd3pMclhxOUNC?= =?utf-8?B?QjhHN09INHdhbng3cStMb2YyK1hmbEx2L1JqMnQ4eWRwS0p5RDhnWHorWHFV?= =?utf-8?B?MXNwT1FkZzdLdFcyOGp0UUJDVjFIRjFhYmFkYklmeE1pMDkrREdMKzZqemV5?= =?utf-8?B?NUlFWERJQXJmUUJwMVZBN0N2M3ZnYlJOVjYvMkUvd3FnT3hMZ0I2alhZdDU1?= =?utf-8?B?UkZENmNxa2RldUM5dFROZEFEVlZmbG9MbHRLNW9QQTY5MmJEclpGNnV3dG1D?= =?utf-8?B?NFRJSFpOV1YzR2xQU3gxSUxlU1hHbVBqREJvTXRnT25PN0V2NXF4MHQ2KzVK?= =?utf-8?B?NjBLYlFJQUtsdkdETXI5UjZodnBUb2MxYWRKMFZzU213RVRDL2pNR2dQSmlq?= =?utf-8?B?TFFiWjhWVUZQTlZUQWtldkVaWHJ1eDJrakFpaVl6MjNhb1FuMkdvNGhhQnZS?= =?utf-8?B?TFRGemJnTHdzUHczYkNUNnduLzZVZDdpcHVCdnVTUWpXUldLdWFxT2lzMnZY?= =?utf-8?B?WVU0N3RoZVBFdUVWdHFvWW1TY3BWUVNTN2N0L01WazdLNkdDYXo0T1lMdjRu?= =?utf-8?B?NmlnajFDKzUrL2UwTzgwejhJdHZMSGZBblB5MFJTYno1L05oNVRKR0NOZUdh?= =?utf-8?B?VitHa3dXUmdLeEdZVnRHMmFzVTJvc0tPN09NVkZmdG5vTEc3eFN0ZWwzN1lJ?= =?utf-8?B?RHhMTVMwN1VMdE9jT1pvVFkvbWNGZjlpeUdhUkdWS1F5amJMZndYSnBnS1lk?= =?utf-8?B?ZnAxMmFzczg2NUVjVnVTMWFXUWl1ZkFPelZZd0FjTDhNMUxEQlhqdDRCRlhk?= =?utf-8?B?eG80WlcrdXpBS2tHMStudG1IWS90MGlodmVjT2JoM21FaWI5cy82QVg1L1BP?= =?utf-8?B?UHpFSldWUWxvSVIzcTkzdStkU0xCRURMWE9qWWFiMHJzcldQbjNHclAwc1Ay?= =?utf-8?B?NnU1c3BPT05uaWw1OFQ0MDd4R0tkaERnYlEvcjkvcEFyWDA0dVF1WDU3ZmZq?= =?utf-8?B?ZDEzc0dmOEYvcUtGeXZEYllVcXlReEtmR2pBWkpIVHcxUDdNYlQvT1pQeHgr?= =?utf-8?B?Yjl3R2Zobk1qZUptZEF5SWJ6UGw4cGkrTEx1Z0JOYmFVLzhPVTlxN1hUak9S?= =?utf-8?B?MFpuc0M0N2JCdlZxQ2VtQW5CTFYrZUt2NE1zWTJqOVZiRnl6K0twQSttWGJS?= =?utf-8?Q?2smPpwI3Vy1txhP7/HjL0ZhZ4nmmoVyIaow6jPN?= X-MS-Exchange-CrossTenant-Network-Message-Id: 7248df02-9891-4445-8d1f-08d904c4f887 X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Apr 2021 12:57:08.2058 (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: YpcIggvtNUI58PxmvzWLPbtGF4hxfohGunfaPhaiyAWgz1vD0VLeEZepLBROt+kO1yzx/YR3BycZbg4dhMc+SA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB4218 X-OriginatorOrg: citrix.com On Wed, Apr 21, 2021 at 12:32:42PM +0200, Jan Beulich wrote: > On 21.04.2021 10:52, Roger Pau Monné wrote: > > On Thu, Apr 01, 2021 at 11:44:45AM +0200, Jan Beulich wrote: > >> PE binaries specify section addresses by (32-bit) RVA. GNU ld up to at > >> least 2.36 would silently truncate the (negative) difference when a > >> section is placed below the image base. Such sections would also be > >> wrongly placed ahead of all "normal" ones. Since, for the time being, > >> we build xen.efi with --strip-debug anyway, .stab* can't appear. And > >> .comment has an entry in /DISCARD/ already anyway in the EFI case. > >> > >> Because of their unclear origin, keep the directives for the ELF case > >> though. > > > > It's my understadng thonse sections are only there for debug purposes, > > and never part of the final xen binary as they are stripped? > > > > Could we maybe remove the section load address of 0 and instead just > > use the (NOLOAD) directive? > > (NOLOAD) is meaningless for PE. > > > Does it really matter to place them at address 0? > > That's the convention for ELF, and also what ld defaults to for debugging > sections. > > > I also wonder, is this change fixing some existing bug, or it's just a > > cleanup change? > > If there were sections at 0, the resulting PE binary would end up broken. > Prior to binutils 2.37 this brokenness is silent, i.e. the linker doesn't > issue any form of diagnostic. The change therefore is addressing a latent > issue - if any such section started being non-empty, we'd be in trouble. > > > I also only see the .comment section in my binary output, so maybe > > it's fine to just remove them from the script? > > Which binary are you referring to - ELF or PE? In the former case, yes, > that's what the statement is for. In the latter case I can't see how this > would be, with .comment being explicitly part of /DISCARD/ in that case. So from a bit of searching I just did it seems like stab sections where used during the 90s with ELF, but that this has long been superseded by DWARF 2 becoming the default in the late 90s, hence I think it would be fine to just remove those sections even in the ELF case? Thanks, Roger.