[Bug c++/99948] New: [modules] ICE in add_mergeable_specialization

["alexander.lelyakin at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99948

            Bug ID: 99948
           Summary: [modules] ICE in add_mergeable_specialization
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: alexander.lelyakin at googlemail dot com
  Target Milestone: ---

/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header sstream
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cwctype
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header iostream
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cmath
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cstdlib
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header cwchar
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header utility
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header memory
/usr/local/bin/g++ -std=c++20 -fmodules-ts -x c++-system-header execution
----
In file included from /usr/local/include/c++/11.0.1/numeric:62,
                 from
/usr/local/include/c++/11.0.1/pstl/parallel_backend_serial.h:16,
                 from /usr/local/include/c++/11.0.1/pstl/parallel_backend.h:14,
                 from /usr/local/include/c++/11.0.1/pstl/algorithm_impl.h:22,
                 from
/usr/local/include/c++/11.0.1/pstl/glue_execution_defs.h:50,
                 from /usr/local/include/c++/11.0.1/execution:32:
/usr/local/include/c++/11.0.1/bits/stl_numeric.h: In function ‘constexpr void
std::iota(_ForwardIterator, _ForwardIterator, _Tp)’:
/usr/local/include/c++/11.0.1/bits/stl_numeric.h:97:25: internal compiler
error: in add_mergeable_specialization, at cp/pt.c:30015
   97 |       for (; __first != __last; ++__first)
      |                         ^~~~~~
0x707243 add_mergeable_specialization(bool, bool, spec_entry*, tree_node*,
unsigned int)
        ../../gcc/gcc/cp/pt.c:30015
0xa770ff trees_in::decl_value()
        ../../gcc/gcc/cp/module.cc:8071
0xa6f617 trees_in::tree_node(bool)
        ../../gcc/gcc/cp/module.cc:9153
0xa75c3b module_state::read_cluster(unsigned int)
        ../../gcc/gcc/cp/module.cc:14811
0xa7613d module_state::load_section(unsigned int, binding_slot*)
        ../../gcc/gcc/cp/module.cc:18082
0xa762f8 lazy_load_binding(unsigned int, tree_node*, tree_node*, binding_slot*)
        ../../gcc/gcc/cp/module.cc:18773
0xa87f2e name_lookup::search_namespace_only(tree_node*)
        ../../gcc/gcc/cp/name-lookup.c:928
0xa8957b name_lookup::search_unqualified(tree_node*, cp_binding_level*)
        ../../gcc/gcc/cp/name-lookup.c:1158
0xa8c284 lookup_name_1
        ../../gcc/gcc/cp/name-lookup.c:7804
0xa8c5fb lookup_name(tree_node*, LOOK_where, LOOK_want)
        ../../gcc/gcc/cp/name-lookup.c:7824
0xa8c5fb lookup_name(tree_node*)
        ../../gcc/gcc/cp/name-lookup.c:7832
0xa8c5fb op_unqualified_lookup
        ../../gcc/gcc/cp/name-lookup.c:9086
0xa8c5fb maybe_save_operator_binding(tree_node*)
        ../../gcc/gcc/cp/name-lookup.c:9148
0xb85b36 build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node**, int)
        ../../gcc/gcc/cp/typeck.c:4302
0xaa3b95 cp_parser_binary_expression
        ../../gcc/gcc/cp/parser.c:10005
0xaa430c cp_parser_assignment_expression
        ../../gcc/gcc/cp/parser.c:10143
0xaa5852 cp_parser_expression
        ../../gcc/gcc/cp/parser.c:10313
0xacbe7a cp_parser_condition
        ../../gcc/gcc/cp/parser.c:12665
0xad6c3b cp_parser_c_for
        ../../gcc/gcc/cp/parser.c:12706
0xad6c3b cp_parser_for
        ../../gcc/gcc/cp/parser.c:12687
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See <https://gcc.gnu.org/bugs/> for instructions.
----
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