[Bug lto/63555] New: ICE compiling simple test with SDB debugging info

[enkovich.gnu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63555

            Bug ID: 63555
           Summary: ICE compiling simple test with SDB debugging info
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: enkovich.gnu at gmail dot com

I see ICE when try to compile a small test with -gcoff.  Problem appears when
we have structure field and static variable with the same name.  Here is a
reproducer:

typedef struct {
  int *next;
} list;

int *next;

int main(int argc, char **argv)
{
  return 0;
}

>gcc -m64 -c -gcoff short.c
cc1: internal compiler error: in needed_p, at cgraphunit.c:237
0x7c1a8c symtab_node::needed_p()
        ../../gcc-pl/gcc/cgraphunit.c:236
0x7c3933 analyze_functions
        ../../gcc-pl/gcc/cgraphunit.c:936
0x7c7579 symbol_table::finalize_compilation_unit()
        ../../gcc-pl/gcc/cgraphunit.c:2288
0x627b77 c_write_global_declarations()
        ../../gcc-pl/gcc/c/c-decl.c:10431
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.

Here is failing assert:

  /* Double check that no one output the function into assembly file            
     early.  */                                                                 
  gcc_checking_assert (!DECL_ASSEMBLER_NAME_SET_P (decl)                        
                       || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME
(decl)));

During file parsing we have a call to sdbout_symbol for structure type.  It
causes output of its field and field's name is marked as referenced.  Later
variable analysis hits assert because variable's assembler name is shared with
the structure field.