[Bug c/70633] New: ICE on valid code at -Os (in 32-bit mode) on x86_64-linux-gnu: output_operand: invalid expression as operand

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70633

            Bug ID: 70633
           Summary: ICE on valid code at -Os (in 32-bit mode) on
                    x86_64-linux-gnu: output_operand: invalid expression
                    as operand
           Product: gcc
           Version: 6.0
            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 code causes an ICE when compiled with the current GCC trunk (and
5.x) at -Os on x86_64-linux-gnu in the 32-bit mode. 

This is a regression from 4.9.x. 


$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/6.0.0/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 6.0.0 20160411 (experimental) [trunk revision 234874] (GCC)
$
$ gcc-trunk -m32 -O0 small.c
$ gcc-4.9 -m32 -Os small.c
$
$ gcc-trunk -m32 -Os small.c
small.c: In function ‘main’:
small.c:10:1: internal compiler error: output_operand: invalid expression as
operand
 }
 ^
0x8610c3 output_operand_lossage(char const*, ...)
        ../../gcc-source-trunk/gcc/final.c:3409
0x861a0d output_addr_const(_IO_FILE*, rtx_def*)
        ../../gcc-source-trunk/gcc/final.c:3998
0xe5291e assemble_integer_with_op(char const*, rtx_def*)
        ../../gcc-source-trunk/gcc/varasm.c:2668
0xe52975 default_assemble_integer(rtx_def*, unsigned int, int)
        ../../gcc-source-trunk/gcc/varasm.c:2684
0xe529fa assemble_integer(rtx_def*, unsigned int, unsigned int, int)
        ../../gcc-source-trunk/gcc/varasm.c:2700
0xe59339 output_constant
        ../../gcc-source-trunk/gcc/varasm.c:4749
0xe5b3ed output_constant
        ../../gcc-source-trunk/gcc/varasm.c:5003
0xe5b3ed output_constructor_regular_field
        ../../gcc-source-trunk/gcc/varasm.c:5006
0xe5b3ed output_constructor
        ../../gcc-source-trunk/gcc/varasm.c:5276
0xe59be0 assemble_constant_contents
        ../../gcc-source-trunk/gcc/varasm.c:3381
0xe624e4 output_constant_def_contents
        ../../gcc-source-trunk/gcc/varasm.c:3426
0xe62768 mark_constants_in_pattern
        ../../gcc-source-trunk/gcc/varasm.c:3951
0xe628db mark_constants
        ../../gcc-source-trunk/gcc/varasm.c:3983
0xe628db mark_constant_pool
        ../../gcc-source-trunk/gcc/varasm.c:3999
0xe628db output_constant_pool
        ../../gcc-source-trunk/gcc/varasm.c:4040
0xe628db assemble_start_function(tree_node*, char const*)
        ../../gcc-source-trunk/gcc/varasm.c:1726
0x864909 rest_of_handle_final
        ../../gcc-source-trunk/gcc/final.c:4439
0x864909 execute
        ../../gcc-source-trunk/gcc/final.c:4516
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.
$


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


int a;

int main ()
{ 
  int __attribute__ ((vector_size (4 * sizeof (int)))) b =
    { (int) main, 0, 0, 0 };
  if (&b + a)
    __builtin_abort ();
  return 0;
}