ROOT Version: 6.28/00 (conda install root -c conda-forge)
Platform: macOS Ventura 13.4
Compiler: Apple clang version 14.0.3 (clang-1403.0.22.14.1)
I have histograms in a ROOT file that was analyzed a few years ago without any problem. But when a new student tried to use it and the analysis macro, he found that the macro always crashes with a segmentation fault.
The code below is a minimum one to reproduce the issue.
void crash () {
auto directory = gDirectory; // crashes
//auto directory = gROOT; // OK
TFile f("test.root");
auto h = (TH1D*)f.Get("signal")->Clone("cloned");
h->SetDirectory(directory);
f.Close();
std::cout << "File closed" << std::endl;
delete h; // crashes here
std::cout << "Cloned histogram has been deleted" << std::endl;
}
In the 2nd line, if I copy gDirectory to directory before opening the ROOT file, deleting the cloned object causes a segmentation fault. But if I copy gROOT to directory, it does not.
In my understanding, saving gDirectory before opening a TFile, namely before switching to another directory, has been a valid and standard step for many years.
What is the problem of my code?
You can download the file from the Dropbox link below.
The issue does not happen when I use another TFile that I created for a test. Therefore maybe the above file is broken.
root [0] .x crash.C
File closed
*** Break *** segmentation violation
[/usr/lib/system/libsystem_platform.dylib] _sigtramp (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TList::AddLast(TObject*) (no debug info)
[<unknown binary>] (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::IncrementalExecutor::executeWrapper(llvm::StringRef, cling::Value*) const (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::Interpreter::RunFunction(clang::FunctionDecl const*, cling::Value*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::Interpreter::EvaluateInternal(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>> const&, cling::CompilationOptions, cling::Value*, cling::Transaction**, unsigned long) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::MetaSema::actOnxCommand(llvm::StringRef, llvm::StringRef, cling::Value*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::MetaParser::isXCommand(cling::MetaSema::ActionResult&, cling::Value*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::MetaParser::isCommand(cling::MetaSema::ActionResult&, cling::Value*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] cling::MetaProcessor::process(llvm::StringRef, cling::Interpreter::CompilationResult&, cling::Value*, bool) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] HandleInterpreterException(cling::MetaProcessor*, char const*, cling::Interpreter::CompilationResult&, cling::Value*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] TCling::ProcessLine(char const*, TInterpreter::EErrorCode*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCling.6.28.00.so] TCling::ProcessLineSynch(char const*, TInterpreter::EErrorCode*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TApplication::ExecuteFile(char const*, int*, bool) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libRint.6.28.00.so] TRint::ProcessLineNr(char const*, char const*, int*) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libRint.6.28.00.so] TRint::HandleTermInput() (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TUnixSystem::CheckDescriptors() (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TMacOSXSystem::DispatchOneEvent(bool) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TSystem::InnerLoop() (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TSystem::Run() (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libCore.6.28.00.so] TApplication::Run(bool) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/lib/libRint.6.28.00.so] TRint::Run(bool) (no debug info)
[/Users/oxon/anaconda3/envs/lab309/bin/root.exe] main (no debug info)
[/usr/lib/dyld] start (no debug info)
Root >