Compilation problem

[makeclean]

Hi All

Ive not had this problem before, so perhaps its time for a module switch for me. Im compiling on an HPC system with openmpi-3.1.3 and gcc-7.2, PETSC builds fine, but libmesh isnt happy

In file included from /home/dc-davi4/moose/moose/scripts/../libmesh/src/systems/system_projection.C:110:0:
./include/libmesh/generic_projector.h: In instantiation of ‘libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const::<lambda(libMesh::processor_id_type, const std::vector<long unsigned int>&)> [with Value = double; FFunctor = libMesh::OldSolutionValue<double, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::processor_id_type = unsigned int]’:
./include/libmesh/generic_projector.h:2853:35:   required from ‘struct libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::OldSolutionValue<double, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>]::<lambda(libMesh::processor_id_type, const class std::vector<long unsigned int>&)>’
./include/libmesh/generic_projector.h:2852:8:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::OldSolutionValue<double, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>]’
./include/libmesh/generic_projector.h:1215:3:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::project(const ConstElemRange&) [with FFunctor = libMesh::OldSolutionValue<double, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::ConstElemRange = libMesh::StoredRange<libMesh::MeshBase::const_element_iterator, const libMesh::Elem*>]’
/home/dc-davi4/moose/moose/scripts/../libmesh/src/systems/system_projection.C:393:48:   required from here
./include/libmesh/generic_projector.h:2871:21: error: uninitialized variable ‘val’ in ‘constexpr’ function
               Value val;
                     ^~~
./include/libmesh/generic_projector.h: In instantiation of ‘libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const::<lambda(libMesh::processor_id_type, const std::vector<long unsigned int>&)> [with Value = double; FFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::TensorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = libMesh::VectorValue<double>; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::processor_id_type = unsigned int]’:
./include/libmesh/generic_projector.h:2853:35:   required from ‘struct libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::TensorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = libMesh::VectorValue<double>; ProjectionAction = libMesh::VectorSetAction<double>]::<lambda(libMesh::processor_id_type, const class std::vector<long unsigned int>&)>’
./include/libmesh/generic_projector.h:2852:8:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::TensorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = libMesh::VectorValue<double>; ProjectionAction = libMesh::VectorSetAction<double>]’
./include/libmesh/generic_projector.h:1215:3:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::project(const ConstElemRange&) [with FFunctor = libMesh::OldSolutionValue<libMesh::VectorValue<double>, &libMesh::FEMContext::point_value>; GFunctor = libMesh::OldSolutionValue<libMesh::TensorValue<double>, &libMesh::FEMContext::point_gradient>; FValue = libMesh::VectorValue<double>; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::ConstElemRange = libMesh::StoredRange<libMesh::MeshBase::const_element_iterator, const libMesh::Elem*>]’
/home/dc-davi4/moose/moose/scripts/../libmesh/src/systems/system_projection.C:404:55:   required from here
./include/libmesh/generic_projector.h:2871:21: error: uninitialized variable ‘val’ in ‘constexpr’ function
./include/libmesh/generic_projector.h: In instantiation of ‘libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const::<lambda(libMesh::processor_id_type, const std::vector<long unsigned int>&)> [with Value = double; FFunctor = libMesh::FEMFunctionWrapper<double>; GFunctor = libMesh::FEMFunctionWrapper<libMesh::VectorValue<double> >; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::processor_id_type = unsigned int]’:
./include/libmesh/generic_projector.h:2853:35:   required from ‘struct libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::FEMFunctionWrapper<double>; GFunctor = libMesh::FEMFunctionWrapper<libMesh::VectorValue<double> >; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>]::<lambda(libMesh::processor_id_type, const class std::vector<long unsigned int>&)>’
./include/libmesh/generic_projector.h:2852:8:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::send_and_insert_dof_values(std::unordered_map<long unsigned int, std::pair<Value, unsigned int> >&, ProjectionAction&) const [with Value = double; FFunctor = libMesh::FEMFunctionWrapper<double>; GFunctor = libMesh::FEMFunctionWrapper<libMesh::VectorValue<double> >; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>]’
./include/libmesh/generic_projector.h:1215:3:   required from ‘void libMesh::GenericProjector<FFunctor, GFunctor, FValue, ProjectionAction>::project(const ConstElemRange&) [with FFunctor = libMesh::FEMFunctionWrapper<double>; GFunctor = libMesh::FEMFunctionWrapper<libMesh::VectorValue<double> >; FValue = double; ProjectionAction = libMesh::VectorSetAction<double>; libMesh::ConstElemRange = libMesh::StoredRange<libMesh::MeshBase::const_element_iterator, const libMesh::Elem*>]’
/home/dc-davi4/moose/moose/scripts/../libmesh/src/systems/system_projection.C:1131:43:   required from here
./include/libmesh/generic_projector.h:2871:21: error: uninitialized variable ‘val’ in ‘constexpr’ function

I have previously compiled on this system using those compilers, but I've since deleted the repo, so I couldnt tell you what the sha was.

[makeclean]

Heres more if this helps

checking for git... (cached) /usr/local/software/global/bin/git

----------------------------------- SUMMARY -----------------------------------

Package version............... : metaphysicl-1.2.1

C++ compiler.................. : mpicxx -std=gnu++17
C++ compiler flags............ : -g -O2 -Wall
Install dir................... : /home/dc-davi4/moose/moose/scripts/../libmesh/installed
Build user.................... : dc-davi4
Build host.................... : login-e-11
Configure date................ : 2021-03-11 09:10
Build architecture............ : x86_64-pc-linux-gnu
Git revision number........... : external

Optional Packages for Testing:
  MASA........................ : no
  VEXCL....................... : no
  TIMPI....................... : no

-------------------------------------------------------------------------------

[milljm]

@lindsayad @roystgnr any ideas on this one?

[roystgnr]

I'm a bit dumbfounded. That's certainly not a constexpr function, and it's okay to have an uninitialized value that later gets written before it's read. I'd be sure this was a compiler bug except that I could swear I used to use gcc 7.2 all the time and never ran into anything like this.

Oh ... wait a minute. I used to use gcc 7.2 all the time, with its default (C++11?) C++ standard settings. What seems to be happening to @makeclean (love the username BTW) is that we're now requesting higher standards by default from compilers that provide them, and gcc 7.2 is probably right at that point where it's trying to support higher standards but not yet doing so reliably. (in fact, ISTR it even having a couple bugs that forced me to upgrade to gcc 8 for an application that needed solid C++14 support; forget about C++17!)

So I think your easiest workaround in this case is to configure libMesh --with-cxx-std=2011 and don't let the compiler try to get fancy on you.

[roystgnr]

Let us know if that works or not. If not, then I certainly wouldn't try to talk you out of simply switching modules to use a newer compiler, but there are other possible workarounds you could try if you wanted to avoid that.

I'm not sure what the best solution here is. I don't want to turn down the default --with-cxx-std-max= setting, but perhaps that's the safest way to go. I'd love to add more tests that could catch problems like this and back off to lower standards at configure time only when necessary, but I can't even imagine how to detect a problem like this. What triggers a level of confusion so deep that it leaves gcc 7.2 unable to tell whether a constexpr keyword is there or not?

[makeclean]

Thanks @roystgnr --with-cxx-std=2011 worked great, in the mean time i built a singularity image, but its always nice to have the bare metal version :)