Doxygen crash with NUM_PROC_THREADS>1

[ferdymercury]

Describe the bug
When building the ROOT project documentation with doxygen, close to the end of the process, we get a crash if we set the NUM_PROC_THREADS to 7. All works perfectly fine if this flag is left at 1.

Expected behavior
No crash is found.

Screenshots

Generating code for file core/base/inc/RQ_OBJECT.h...
Generating code for file core/base/inc/RStipples.h...
Generating code for file core/base/inc/Rtypes.h...
Generating code for file core/base/inc/RtypesImp.h...
Generating code for file core/base/inc/Strlen.h...
Generating code for file core/base/inc/TApplication.h...
Generating code for file core/base/inc/TAtt3D.h...
Generating code for file core/base/inc/TAttAxis.h...
error: Could not open file /home/ferhue/rootdoc/html/RDrawableRequest_8cxx_source.html for writing
Exiting...
Generating code for file core/base/inc/TAttBBox.h...
error: could not open file /opt/root_src/core/base/inc/TAttBBox.h
error: cannot open file '/opt/root_src/core/base/inc/TAttBBox.h' for reading
Generating code for file core/base/inc/TAttBBox2D.h...
error: could not open file /opt/root_src/core/base/inc/TAttBBox2D.h
error: cannot open file '/opt/root_src/core/base/inc/TAttBBox2D.h' for reading
Generating code for file core/base/inc/TAttFill.h...
error: could not open file /opt/root_src/core/base/inc/TAttFill.h
error: cannot open file '/opt/root_src/core/base/inc/TAttFill.h' for reading
Generating code for file core/base/inc/TAttLine.h...
error: could not open file /opt/root_src/core/base/inc/TAttLine.h
error: cannot open file '/opt/root_src/core/base/inc/TAttLine.h' for reading
Generating code for file core/base/inc/TAttMarker.h...
error: could not open file /opt/root_src/core/base/inc/TAttMarker.h
error: cannot open file '/opt/root_src/core/base/inc/TAttMarker.h' for reading
Generating code for file core/base/inc/TAttPad.h...
error: could not open file /opt/root_src/core/base/inc/TAttPad.h
error: cannot open file '/opt/root_src/core/base/inc/TAttPad.h' for reading
Generating code for file core/base/inc/TAttText.h...
error: could not open file /opt/root_src/core/base/inc/TAttText.h
error: cannot open file '/opt/root_src/core/base/inc/TAttText.h' for reading
Generating code for file core/base/inc/TBase64.h...
error: could not open file /opt/root_src/core/base/inc/TBase64.h
error: cannot open file '/opt/root_src/core/base/inc/TBase64.h' for reading
Generating code for file core/base/inc/TBenchmark.h...
error: could not open file /opt/root_src/core/base/inc/TBenchmark.h
error: cannot open file '/opt/root_src/core/base/inc/TBenchmark.h' for reading
Generating code for file core/base/inc/TBuffer.h...
error: could not open file /opt/root_src/core/base/inc/TBuffer.h
error: cannot open file '/opt/root_src/core/base/inc/TBuffer.h' for reading
Generating code for file core/base/inc/TBuffer3D.h...
error: could not open file /opt/root_src/core/base/inc/TBuffer3D.h
error: cannot open file '/opt/root_src/core/base/inc/TBuffer3D.h' for reading
Generating code for file core/base/inc/TBuffer3DTypes.h...
error: could not open file /opt/root_src/core/base/inc/TBuffer3DTypes.h
error: cannot open file '/opt/root_src/core/base/inc/TBuffer3DTypes.h' for reading
Generating code for file core/base/inc/TColor.h...
error: could not open file /opt/root_src/core/base/inc/TColor.h
error: cannot open file '/opt/root_src/core/base/inc/TColor.h' for reading
Generating code for file core/base/inc/TColorGradient.h...
error: could not open file /opt/root_src/core/base/inc/TColorGradient.h
error: cannot open file '/opt/root_src/core/base/inc/TColorGradient.h' for reading
Generating code for file core/base/inc/TDatime.h...
error: could not open file /opt/root_src/core/base/inc/TDatime.h
error: cannot open file '/opt/root_src/core/base/inc/TDatime.h' for reading
Generating code for file core/base/inc/TDirectory.h...
error: could not open file /opt/root_src/core/base/inc/TDirectory.h
error: cannot open file '/opt/root_src/core/base/inc/TDirectory.h' for reading
Generating code for file core/base/inc/TEnv.h...
error: could not open file /opt/root_src/core/base/inc/TEnv.h
error: cannot open file '/opt/root_src/core/base/inc/TEnv.h' for reading
Generating code for file core/base/inc/TException.h...
error: could not open file /opt/root_src/core/base/inc/TException.h
error: cannot open file '/opt/root_src/core/base/inc/TException.h' for reading
Generating code for file core/base/inc/TExec.h...
error: could not open file /opt/root_src/core/base/inc/TExec.h
error: cannot open file '/opt/root_src/core/base/inc/TExec.h' for reading
Generating code for file core/base/inc/TFileCollection.h...
error: could not open file /opt/root_src/core/base/inc/TFileCollection.h
error: cannot open file '/opt/root_src/core/base/inc/TFileCollection.h' for reading
Generating code for file core/base/inc/TFileInfo.h...
error: could not open file /opt/root_src/core/base/inc/TFileInfo.h
error: cannot open file '/opt/root_src/core/base/inc/TFileInfo.h' for reading
Generating code for file core/base/inc/TFolder.h...
error: could not open file /opt/root_src/core/base/inc/TFolder.h
error: cannot open file '/opt/root_src/core/base/inc/TFolder.h' for reading
Generating code for file core/base/inc/TInetAddress.h...
error: could not open file /opt/root_src/core/base/inc/TInetAddress.h
error: cannot open file '/opt/root_src/core/base/inc/TInetAddress.h' for reading
Generating code for file core/base/inc/TMacro.h...
error: could not open file /opt/root_src/core/base/inc/TMacro.h
error: cannot open file '/opt/root_src/core/base/inc/TMacro.h' for reading
Generating code for file core/base/inc/TMathBase.h...
error: could not open file /opt/root_src/core/base/inc/TMathBase.h
error: cannot open file '/opt/root_src/core/base/inc/TMathBase.h' for reading
Generating code for file core/base/inc/TMD5.h...
error: could not open file /opt/root_src/core/base/inc/TMD5.h
error: cannot open file '/opt/root_src/core/base/inc/TMD5.h' for reading
Generating code for file core/base/inc/TMemberInspector.h...
error: could not open file /opt/root_src/core/base/inc/TMemberInspector.h
error: cannot open file '/opt/root_src/core/base/inc/TMemberInspector.h' for reading
Generating code for file core/base/inc/TMessageHandler.h...
error: could not open file /opt/root_src/core/base/inc/TMessageHandler.h
error: cannot open file '/opt/root_src/core/base/inc/TMessageHandler.h' for reading
Generating code for file core/base/inc/TNamed.h...
error: could not open file /opt/root_src/core/base/inc/TNamed.h
error: cannot open file '/opt/root_src/core/base/inc/TNamed.h' for reading
Generating code for file core/base/inc/TNotifyLink.h...
error: could not open file /opt/root_src/core/base/inc/TNotifyLink.h
error: cannot open file '/opt/root_src/core/base/inc/TNotifyLink.h' for reading
Generating code for file core/base/inc/TObject.h...
error: could not open file /opt/root_src/core/base/inc/TObject.h
error: cannot open file '/opt/root_src/core/base/inc/TObject.h' for reading
Generating code for file core/base/inc/TObjString.h...
error: could not open file /opt/root_src/core/base/inc/TObjString.h
error: cannot open file '/opt/root_src/core/base/inc/TObjString.h' for reading
Generating code for file core/base/inc/TParameter.h...
error: could not open file /opt/root_src/core/base/inc/TParameter.h
error: cannot open file '/opt/root_src/core/base/inc/TParameter.h' for reading
Generating code for file core/base/inc/TPluginManager.h...
error: could not open file /opt/root_src/core/base/inc/TPluginManager.h
error: cannot open file '/opt/root_src/core/base/inc/TPluginManager.h' for reading
Generating code for file core/base/inc/TPoint.h...
error: could not open file /opt/root_src/core/base/inc/TPoint.h
error: cannot open file '/opt/root_src/core/base/inc/TPoint.h' for reading
Generating code for file core/base/inc/TPRegexp.h...
error: could not open file /opt/root_src/core/base/inc/TPRegexp.h
error: cannot open file '/opt/root_src/core/base/inc/TPRegexp.h' for reading
Generating code for file core/base/inc/TProcessID.h...
error: could not open file /opt/root_src/core/base/inc/TProcessID.h
error: cannot open file '/opt/root_src/core/base/inc/TProcessID.h' for reading
Generating code for file core/base/inc/TProcessUUID.h...
error: could not open file /opt/root_src/core/base/inc/TProcessUUID.h
error: cannot open file '/opt/root_src/core/base/inc/TProcessUUID.h' for reading
Generating code for file core/base/inc/TQClass.h...
error: could not open file /opt/root_src/core/base/inc/TQClass.h
error: cannot open file '/opt/root_src/core/base/inc/TQClass.h' for reading
Generating code for file core/base/inc/TQCommand.h...
error: could not open file /opt/root_src/core/base/inc/TQCommand.h
error: cannot open file '/opt/root_src/core/base/inc/TQCommand.h' for reading
Generating code for file core/base/inc/TQConnection.h...
error: could not open file /opt/root_src/core/base/inc/TQConnection.h
error: cannot open file '/opt/root_src/core/base/inc/TQConnection.h' for reading
Generating code for file core/base/inc/TQObject.h...
error: could not open file /opt/root_src/core/base/inc/TQObject.h
error: cannot open file '/opt/root_src/core/base/inc/TQObject.h' for reading
Generating code for file core/base/inc/TRedirectOutputGuard.h...
error: could not open file /opt/root_src/core/base/inc/TRedirectOutputGuard.h
error: cannot open file '/opt/root_src/core/base/inc/TRedirectOutputGuard.h' for reading
Generating code for file core/base/inc/TRef.h...
error: could not open file /opt/root_src/core/base/inc/TRef.h
error: cannot open file '/opt/root_src/core/base/inc/TRef.h' for reading
Generating code for file core/base/inc/TRefCnt.h...
error: could not open file /opt/root_src/core/base/inc/TRefCnt.h
error: cannot open file '/opt/root_src/core/base/inc/TRefCnt.h' for reading
Generating code for file core/base/inc/TRegexp.h...
error: could not open file /opt/root_src/core/base/inc/TRegexp.h
error: cannot open file '/opt/root_src/core/base/inc/TRegexp.h' for reading
Generating code for file core/base/inc/TRemoteObject.h...
error: could not open file /opt/root_src/core/base/inc/TRemoteObject.h
error: cannot open file '/opt/root_src/core/base/inc/TRemoteObject.h' for reading
Generating code for file core/base/inc/TROOT.h...
error: could not open file /opt/root_src/core/base/inc/TROOT.h
error: cannot open file '/opt/root_src/core/base/inc/TROOT.h' for reading
Generating code for file core/base/inc/TRootIOCtor.h...
error: could not open file /opt/root_src/core/base/inc/TRootIOCtor.h
error: cannot open file '/opt/root_src/core/base/inc/TRootIOCtor.h' for reading
Generating code for file core/base/inc/TStopwatch.h...
error: could not open file /opt/root_src/core/base/inc/TStopwatch.h
error: cannot open file '/opt/root_src/core/base/inc/TStopwatch.h' for reading
Generating code for file core/base/inc/TStorage.h...
error: could not open file /opt/root_src/core/base/inc/TStorage.h
error: cannot open file '/opt/root_src/core/base/inc/TStorage.h' for reading
Generating code for file core/base/inc/TString.h...
error: could not open file /opt/root_src/core/base/inc/TString.h
error: cannot open file '/opt/root_src/core/base/inc/TString.h' for reading
Generating code for file core/base/inc/TStringLong.h...
error: could not open file /opt/root_src/core/base/inc/TStringLong.h
error: cannot open file '/opt/root_src/core/base/inc/TStringLong.h' for reading
Generating code for file core/base/inc/TStyle.h...
error: could not open file /opt/root_src/core/base/inc/TStyle.h
error: cannot open file '/opt/root_src/core/base/inc/TStyle.h' for reading
Generating code for file core/base/inc/TSysEvtHandler.h...
error: could not open file /opt/root_src/core/base/inc/TSysEvtHandler.h
error: cannot open file '/opt/root_src/core/base/inc/TSysEvtHandler.h' for reading
Generating code for file core/base/inc/TSystem.h...
error: could not open file /opt/root_src/core/base/inc/TSystem.h
error: cannot open file '/opt/root_src/core/base/inc/TSystem.h' for reading
Generating code for file core/base/inc/TSystemDirectory.h...
error: could not open file /opt/root_src/core/base/inc/TSystemDirectory.h
error: cannot open file '/opt/root_src/core/base/inc/TSystemDirectory.h' for reading
Generating code for file core/base/inc/TSystemFile.h...
error: could not open file /opt/root_src/core/base/inc/TSystemFile.h
error: cannot open file '/opt/root_src/core/base/inc/TSystemFile.h' for reading
Generating code for file core/base/inc/TTask.h...

Thread 14 "doxygen" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff6a74700 (LWP 4696)]
0x0000555555a5d81a in std::vector<reg::PToken, std::allocator<reg::PToken> >::size (this=0x8) at /usr/include/c++/8/bits/stl_vector.h:806
806	      { return size_type(this->_M_impl._M_finish - this->_M_impl._M_start); }

Of course, all these files above exist and are readable. (It works well in single-thread).

If I build doxygen in Release Mode, I only see a couple of these messages before the crash, rather than so many.

To Reproduce
It can be reproduced by following the build instructions and setting in the Doxyfile NUM_PROC_THREADS to 7.

Version
1.9.4 (f1e207a*)

Stack trace
stacktrace.txt.zip

Additional context
RAM memory is fine, no signs of memleaks.
I tried fixing our filter adding some read-write safeguards, but there is no difference in the final result. root-project/root#9983

[ferdymercury]

Sorry, duplicate, GitHub was hanging

[doxygen]

@ferdymercury Still have to look in detail, but just looking at the output, I'd say the problem is that doxygen leaks open file handles until the system runs out (just a theory for now, to be confirmed).

[doxygen]

@ferdymercury Please check if the referenced commit fixes the problem. I have tested it on doxygen's own sources only so far, not yet on the root package.

[albert-github]

I saw that there was some things done with Fortran as well so I wrote a quick test procedure:

!> \file
!> Test for return type of Fortran


!> Normal subroutine
!> \param a the parameter
subroutine fie_ok(a)
  integer:: a
end subroutine

!> Return shown subroutine
!> \param a the parameter
!> \return should trigger a warning
subroutine fie_err(a)
  integer:: a
end subroutine

this gives in the old situation, correctly:

.../aa.f90:12: warning: documented empty return type of fie_err

but in the situation with the update the message is missing.

Example: example.tar.gz

[doxygen]

@albert-github I see the corresponding warning now only appears if WARN_NO_PARAMDOC=YES.
Should be corrected with commit 379bd0e

Before that, this warning was given as part of the detection routine, which was not the right place.

[albert-github]

When I now have WARN_NO_PARAMDOC=NO I see the message regarding line 12 and I aslso see this message when WARN_NO_PARAMDOC = YES but in the later case I also see the warning:

.../aa.f90:6: warning: return type of member fie_ok is not documented

and this is not correct.

[doxygen]

@albert-github Indeed, made this commit to properly guard the warning. Let me know if I still missed anything.

[albert-github]

Checked with a bit more extensive example (but still small) and this looks OK.

[ferdymercury]

Thanks for the investigation!

I rebuilt, and I get this error printed out:
Generating docs for fdoxygen: /opt/doxygen/src/dot.cpp:150: DotFilePatcher* DotManager::createFilePatcher(const QCString&): Assertion rv.second' failed.`

It hangs there for a couple of minutes, and then it crashes as follows:

Makefile:49: recipe for target 'doxygen' failed
make: *** [doxygen] Aborted (core dumped)
22:59:48: The process "/usr/bin/make" exited with code 2.

[ferdymercury]

If I run with the debugger, I get:

doxygen: /opt/doxygen/src/dot.cpp:150: DotFilePatcher* DotManager::createFilePatcher(const QCString&): Assertion `rv.second' failed.
Generating docs for file graf3d/g3d/inc/THelix.h...
Generating docs for file graf3d/g3d/inc/THYPE.h...
Generating docs for file graf3d/g3d/inc/TMarker3DBox.h...
Generating docs for file graf3d/g3d/inc/TMaterial.h...

Thread 22 "doxygen" received signal SIGABRT, Aborted.
[Switching to Thread 0x7ffff426f700 (LWP 16662)]
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
51	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.

The backtrace is attached here bt.txt.zip. Apparently there are 80+ threads being defined, even if I only specified NUM_PROC_THREADS = 7.