septum 0.0.7

We encountered an error during the generation of documentation:
<ProtectedTypeDecl ["Async_File_Cache"] sp-cache.ads:53:5-78:26> <<<<<
<DefiningName sp-cache.ads:53:20-53:36> <<<<<
<Id "Async_File_Cache" sp-cache.ads:53:20-53:36> <<<<<
<ParentList sp-cache.ads:53:36-53:36> <<<<<
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<DeclList sp-cache.ads:75:9-77:34> <<<<<
<ComponentDecl ["Top_Level_Directories"] sp-cache.ads:75:9-75:60> <<<<<
<DefiningNameList sp-cache.ads:75:9-75:30> <<<<<
<DefiningName sp-cache.ads:75:9-75:30> <<<<<
<Id "Top_Level_Directories" sp-cache.ads:75:9-75:30> <<<<<
<ComponentDef sp-cache.ads:75:33-75:59> <<<<<
<AliasedAbsent sp-cache.ads:75:32-75:32> <<<<<
<ConstantAbsent sp-cache.ads:75:32-75:32> <<<<<
<SubtypeIndication sp-cache.ads:75:33-75:59> <<<<<
<NotNullAbsent sp-cache.ads:75:32-75:32> <<<<<
<DottedName sp-cache.ads:75:33-75:59> <<<<<
<DottedName sp-cache.ads:75:33-75:55> <<<<<
<DottedName sp-cache.ads:75:33-75:43> <<<<<
<Id "SP" sp-cache.ads:75:33-75:35> <<<<<
<Id "Strings" sp-cache.ads:75:36-75:43> <<<<<
<Id "String_Sets" sp-cache.ads:75:44-75:55> <<<<<
<Id "Set" sp-cache.ads:75:56-75:59> <<<<<
<ComponentDecl ["Contents"] sp-cache.ads:77:9-77:34> <<<<<
<DefiningNameList sp-cache.ads:77:9-77:17> <<<<<
<DefiningName sp-cache.ads:77:9-77:17> <<<<<
<Id "Contents" sp-cache.ads:77:9-77:17> <<<<<
<ComponentDef sp-cache.ads:77:20-77:33> <<<<<
<AliasedAbsent sp-cache.ads:77:19-77:19> <<<<<
<ConstantAbsent sp-cache.ads:77:19-77:19> <<<<<
<SubtypeIndication sp-cache.ads:77:20-77:33> <<<<<
<NotNullAbsent sp-cache.ads:77:19-77:19> <<<<<
<DottedName sp-cache.ads:77:20-77:33> <<<<<
<Id "File_Maps" sp-cache.ads:77:20-77:29> <<<<<
<Id "Map" sp-cache.ads:77:30-77:33> <<<<<
<EndName sp-cache.ads:78:9-78:25> <<<<<
<Id "Async_File_Cache" sp-cache.ads:78:9-78:25> <<<<<
<PackageRenamingDecl ["PI"] sp-progress.ads:5:5-5:44>
<TaskTypeDecl ["Update_Progress"] sp-progress.ads:7:5-9:25> <<<<<
<DefiningName sp-progress.ads:7:15-7:30> <<<<<
<Id "Update_Progress" sp-progress.ads:7:15-7:30> <<<<<
<KnownDiscriminantPart sp-progress.ads:7:31-7:76> <<<<<
<DiscriminantSpecList sp-progress.ads:7:32-7:75> <<<<<
<DiscriminantSpec ["Work"] sp-progress.ads:7:32-7:75> <<<<<
<DefiningNameList sp-progress.ads:7:32-7:36> <<<<<
<DefiningName sp-progress.ads:7:32-7:36> <<<<<
<Id "Work" sp-progress.ads:7:32-7:36> <<<<<
<AnonymousType sp-progress.ads:7:39-7:75> <<<<<

raised LANGKIT_SUPPORT.ERRORS.PRECONDITION_FAILURE : null node argument
ERROR: Command ["gnatdoc4", "-P", "septum.gpr", "--output-dir", "/home/chouteau/src/github/alire/docs.ada.dev/crate/septum/0.0.7", "--front-matter", "crate: septum", "--no-subprojects"] exited with code 1