potential null pointer dereference

Summary

Compiler warnings

Environment

• Operating System : Linux
• Architecture : x64
• Eigen Version :

commit d34b100c137ac931379ae5e1b888f16a9c8d6c72 (HEAD)
Author: Charles Schlosser <cs.schlosser@gmail.com>
Date:   Wed Nov 27 19:32:14 2024 +0000

    Fix UB in setZero

• Compiler Version :

/usr/tce/packages/rocm/rocm-6.4.0alpha3/bin/amdclang++ --version
AMD clang version 20.0.0git (ssh://gerritgit/lightning/ec/llvm-project amd-staging 24371 986f979d075ccab39a6e5babbfd6db4723753bbf)
Target: x86_64-unknown-linux-gnu
Thread model: posix

• Compile Flags : -O3 -march=native

        "CXX_STANDARD": "17",

Minimal Example

eigen3/Eigen/src/Core/CoreEvaluators.h:1026:48: warning: potential null pointer dereference [-Wnull-dereference]
 1026 |     return m_data[index * m_innerStride.value()];
      |                                                ^

eigen3/unsupported/Eigen/CXX11/src/Tensor/TensorContraction.h:494:51: warning: null pointer dereference [-Wnull-dereference]
  494 |         m_left_nocontract_strides[nocontract_idx] = lhs_strides[i];
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~

/eigen3/unsupported/Eigen/CXX11/../../../Eigen/src/Core/functors/BinaryFunctors.h:80:14: warning: potential null pointer dereference [-Wnull-dereference]
   80 |     return a * b;
      |            ~~^~~