[Bug c++/71828] New: ICE on valid C++11 code with __Complex int variable declaration: in operand_equal_p, at fold-const.c:2790

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71828

            Bug ID: 71828
           Summary: ICE on valid C++11 code with __Complex int variable
                    declaration: in operand_equal_p, at fold-const.c:2790
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

The following C++11 code causes an ICE when compiled with the current GCC trunk
on x86_64-linux-gnu in both 32-bit and 64-bit modes.  

This is a regression from 6.1.x.


$ g++-trunk -v
Using built-in specs.
COLLECT_GCC=g++-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/usr/local/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 7.0.0 20160709 (experimental) [trunk revision 238191] (GCC) 
$ 
$ g++-6.1 -c small.cpp
$ 
$ g++-trunk -c small.cpp
small.cpp:3:44: internal compiler error: in operand_equal_p, at
fold-const.c:2790
 static_assert (& __imag a == &__real a, "");
                                            ^
0xab89b0 operand_equal_p(tree_node const*, tree_node const*, unsigned int)
        ../../gcc-source-trunk/gcc/fold-const.c:2790
0xab70e9 operand_equal_p(tree_node const*, tree_node const*, unsigned int)
        ../../gcc-source-trunk/gcc/fold-const.c:2951
0xab6cbf operand_equal_p(tree_node const*, tree_node const*, unsigned int)
        ../../gcc-source-trunk/gcc/fold-const.c:2749
0x1226391 generic_simplify_EQ_EXPR
        /tmp/gcc-builder/gcc-build-trunk/gcc/generic-match.c:27436
0x122ab55 generic_simplify(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*)
        /tmp/gcc-builder/gcc-build-trunk/gcc/generic-match.c:31021
0xac73f7 fold_binary_loc(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*)
        ../../gcc-source-trunk/gcc/fold-const.c:9161
0x8aeba8 cxx_eval_binary_expression
        ../../gcc-source-trunk/gcc/cp/constexpr.c:1816
0x8ab4d7 cxx_eval_constant_expression
        ../../gcc-source-trunk/gcc/cp/constexpr.c:3885
0x8b1ec9 cxx_eval_outermost_constant_expr
        ../../gcc-source-trunk/gcc/cp/constexpr.c:4211
0x8b4ec8 maybe_constant_value_1
        ../../gcc-source-trunk/gcc/cp/constexpr.c:4405
0x8b4ec8 maybe_constant_value(tree_node*, tree_node*)
        ../../gcc-source-trunk/gcc/cp/constexpr.c:4429
0x81ded5 finish_static_assert(tree_node*, tree_node*, unsigned int, bool)
        ../../gcc-source-trunk/gcc/cp/semantics.c:8749
0x79c370 cp_parser_static_assert
        ../../gcc-source-trunk/gcc/cp/parser.c:13056
0x7ae489 cp_parser_block_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12247
0x7b6d50 cp_parser_declaration
        ../../gcc-source-trunk/gcc/cp/parser.c:12148
0x7b5824 cp_parser_declaration_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:12027
0x7b5b58 cp_parser_translation_unit
        ../../gcc-source-trunk/gcc/cp/parser.c:4329
0x7b5b58 c_parse_file()
        ../../gcc-source-trunk/gcc/cp/parser.c:37505
0x919dc2 c_common_parse_file()
        ../../gcc-source-trunk/gcc/c-family/c-opts.c:1070
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
$ 


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


constexpr _Complex int a {1, 1};

static_assert (& __imag a == &__real a, "");