[tree] setup reader proxy when registering after constructor

ferdymercury · dpiparo · commit 65cdfb45b167 · 2025-12-15T15:24:15.000+01:00
Fixes https://its.cern.ch/jira/browse/ROOT-8842
diff --git a/tree/treeplayer/src/TTreeReaderFast.cxx b/tree/treeplayer/src/TTreeReaderFast.cxx
@@ -121,6 +121,13 @@ TTreeReaderFast::SetEntry(Long64_t entry)
 void TTreeReaderFast::RegisterValueReader(ROOT::Experimental::Internal::TTreeReaderValueFastBase* reader)
 {
    fValues.push_back(reader);
+   if (fTree && reader) { // A subpart of Initialize() must be called if we register new readers after the constructor.
+      reader->CreateProxy();
+      if (reader->GetSetupStatus() != ROOT::Internal::TTreeReaderValueBase::kSetupMatch) {
+         //printf("Reader setup failed.  Status: %d\n", reader->GetSetupStatus());
+         fEntryStatus = TTreeReader::kEntryBadReader;
+      }
+   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////

Original file line number	Diff line number	Diff line change
`@@ -121,6 +121,13 @@ TTreeReaderFast::SetEntry(Long64_t entry)`
`121`	`121`	`void TTreeReaderFast::RegisterValueReader(ROOT::Experimental::Internal::TTreeReaderValueFastBase* reader)`
`122`	`122`	`{`
`123`	`123`	`fValues.push_back(reader);`
	`124`	`+ if (fTree && reader) { // A subpart of Initialize() must be called if we register new readers after the constructor.`
	`125`	`+ reader->CreateProxy();`
	`126`	`+ if (reader->GetSetupStatus() != ROOT::Internal::TTreeReaderValueBase::kSetupMatch) {`
	`127`	`+ //printf("Reader setup failed. Status: %d\n", reader->GetSetupStatus());`
	`128`	`+ fEntryStatus = TTreeReader::kEntryBadReader;`
	`129`	`+ }`
	`130`	`+ }`
`124`	`131`	`}`
`125`	`132`
`126`	`133`	`////////////////////////////////////////////////////////////////////////////////`