https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96354
--- Comment #2 from Tiziano Müller <t...@dev-zero.ch> --- (In reply to Martin Liška from comment #1) > Can you please provide steps how to build the project? I can reproduce it > locally then. Of course! :) After unpacking you don't even have to configure it, simply doing the following is enough. Note: it is only with the combination '-O2', '-g', '-fopenmp', leaving away any one of them makes it build. $ cd plumed-2.6.1/src/tools $ c++ --version c++ (GCC) 10.2.0 Copyright (C) 2020 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ c++ -I.. -c -O2 -g -std=c++11 -fopenmp RMSD.cpp -o RMSD.o during IPA pass: inline RMSD.cpp: In member function ‘void PLMD::RMSDCoreData::doCoreCalcWithCloseStructure(bool, bool, PLMD::Tensor&, PLMD::Tensor&, std::array<std::array<PLMD::TensorGeneric<3, 3>, 3>, 3>&)’: RMSD.cpp:1134:6: internal compiler error: in maybe_canonicalize_mem_ref_addr, at gimple-fold.c:4903 1134 | void RMSDCoreData::doCoreCalcWithCloseStructure(bool safe,bool alEqDis, Tensor & rotationPosClose, Tensor & rotationRefClose, std::array<std::array<Tensor,3>,3> & drotationPosCloseDrr01) { | ^~~~~~~~~~~~ 0xa1bdac maybe_canonicalize_mem_ref_addr /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/gimple-fold.c:4903 0xa20553 fold_stmt_1 /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/gimple-fold.c:5058 0xd26380 fold_marked_statements /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/tree-inline.c:5342 0xd332b5 optimize_inline_calls(tree_node*) /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/tree-inline.c:5448 0xac9f9e inline_transform(cgraph_node*) /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/ipa-inline-transform.c:736 0xbf187e execute_one_ipa_transform_pass /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/passes.c:2233 0xbf187e execute_all_ipa_transforms(bool) /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/passes.c:2272 0x8dfdc4 cgraph_node::expand() /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/cgraphunit.c:2293 0x8e117d expand_all_functions /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/cgraphunit.c:2471 0x8e117d symbol_table::compile() /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/cgraphunit.c:2822 0x8e325c symbol_table::finalize_compilation_unit() /data/tiziano/cp2k/tools/toolchain/build/gcc-10.2.0/gcc/cgraphunit.c:3002 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions.