[Bug c++/95844] New: [11 Regression] ICE: Segmentation fault (in cp_warn_deprecated_use)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95844

            Bug ID: 95844
           Summary: [11 Regression] ICE: Segmentation fault (in
                    cp_warn_deprecated_use)
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-11.0.0-alpha20200621 snapshot (g:47ddb895df311e546a6f54345e18b8749ac50324)
ICEs when compiling the following testcase, extracted from
test/CXX/class/class.compare/class.compare.default/p4.cpp from the clang 10.0.0
test suite, w/ -std=c++20 -Wdeprecated-copy:

namespace std {
  struct strong_ordering {
  };
}

struct F {
  [[deprecated("oh no")]] std::strong_ordering operator<=>(const F&) const =
default;
};
void use_f(F f) {
  void(f == f);
}

% g++-11.0.0 -std=c++20 -Wdeprecated-copy -c uwfljn63.cpp
uwfljn63.cpp: In function 'void use_f(F)':
uwfljn63.cpp:10:13: internal compiler error: Segmentation fault
   10 |   void(f == f);
      |             ^
0x100872f crash_signal
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/toplev.c:328
0x9277f3 cp_warn_deprecated_use(tree_node*, int)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/decl2.c:5426
0x92fb8e cp_warn_deprecated_use(tree_node*, int)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/decl2.c:5393
0x92fb8e mark_used(tree_node*, int)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/decl2.c:5547
0x880abb build_over_call
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/call.c:9064
0x888553 build_new_op_1
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/call.c:6341
0x888d6d build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node**, int)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/call.c:6605
0xa75a0d build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node**, int)
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/typeck.c:4280
0x99bf34 cp_parser_binary_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:9777
0x99da2e cp_parser_assignment_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:9914
0x9a09a0 cp_parser_parenthesized_expression_list
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:8031
0x9a11f0 cp_parser_functional_cast
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:29643
0x9b9d44 cp_parser_postfix_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:7219
0x99bd79 cp_parser_binary_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:9609
0x99da2e cp_parser_assignment_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:9914
0x99ddf3 cp_parser_expression
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:10082
0x9a0da8 cp_parser_expression_statement
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:11742
0x9ac443 cp_parser_statement
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:11538
0x9adcf8 cp_parser_statement_seq_opt
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:11889
0x9addd8 cp_parser_compound_statement
       
/var/tmp/portage/sys-devel/gcc-11.0.0_alpha20200621/work/gcc-11-20200621/gcc/cp/parser.c:11839