[Bug c++/83588] [6/7/8 Regression] struct with two flexible arrays causes an internal compiler error

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83588

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|accepts-invalid             |
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-01-14
                 CC|                            |msebor at gcc dot gnu.org
            Summary|Struct with two flexible    |[6/7/8 Regression] struct
                   |arrays causes an internal   |with two flexible arrays
                   |compiler error              |causes an internal compiler
                   |                            |error
     Ever confirmed|0                           |1
      Known to fail|                            |6.4.0, 7.2.0, 8.0

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
Confirmed with GCC 6, 7, and 8.  Bisection points to r231665.  Initialization
of objects with flexible array members is accepted for compatibility with GCC.

$ cat pr83588.C && gcc -S -Wall pr83588.C.

struct Foo                                                                      
{
  int i, a[], b[];
};                                                                          

struct Foo t = {1, {0, 0, 0}, {0, 0, 0}}; 
pr83588.C:6:41: internal compiler error: in output_constructor_regular_field,
at varasm.c:5155
 struct Foo t = {1, {0, 0, 0}, {0, 0, 0}};
                                         ^
0x16c5a99 output_constructor_regular_field
        /ssd/src/gcc/git/gcc/varasm.c:5155
0x16c6729 output_constructor
        /ssd/src/gcc/git/gcc/varasm.c:5438
0x16c5090 output_constant
        /ssd/src/gcc/git/gcc/varasm.c:4965
0x16baa3d assemble_variable_contents
        /ssd/src/gcc/git/gcc/varasm.c:2134
0x16bb549 assemble_variable(tree_node*, int, int, int)
        /ssd/src/gcc/git/gcc/varasm.c:2310
0x16d555e varpool_node::assemble_decl()
        /ssd/src/gcc/git/gcc/varpool.c:590
0xcad84b output_in_order
        /ssd/src/gcc/git/gcc/cgraphunit.c:2385
0xcae001 symbol_table::compile()
        /ssd/src/gcc/git/gcc/cgraphunit.c:2623
0xcae2c1 symbol_table::finalize_compilation_unit()
        /ssd/src/gcc/git/gcc/cgraphunit.c:2717
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