[Bug rtl-optimization/70396] New: ICE on valid code at -O3 in 32-bit and 64-bit modes on x86_64-linux-gnu (in immed_wide_int_const, at emit-rtl.c:606)

["chengniansun at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70396

            Bug ID: 70396
           Summary: ICE on valid code at -O3 in 32-bit and 64-bit modes on
                    x86_64-linux-gnu (in immed_wide_int_const, at
                    emit-rtl.c:606)
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: chengniansun at gmail dot com
  Target Milestone: ---

The following code crashes the trunk at -O3 in 32-bit and 64-bit modes on
x86_64-linux-gnu.



$: 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
Thread model: posix
gcc version 6.0.0 20160324 (experimental) [trunk revision 234448] (GCC) 
$: 
$: gcc-trunk -O3 small.c
small.c:4:5: warning: array âaâ assumed to have one element
 int a[];
     ^
small.c: In function âfn1â:
small.c:11:14: warning: iteration 2147483645 invokes undefined behavior
[-Waggressive-loop-optimizations]
   for (; c; c++) {
             ~^~
small.c:11:3: note: within this loop
   for (; c; c++) {
   ^~~
small.c:7:6: internal compiler error: in immed_wide_int_const, at
emit-rtl.c:606
 void fn1() {
      ^~~
0x806f7d immed_wide_int_const(generic_wide_int<wide_int_ref_storage<false> >
const&, machine_mode)
        ../../gcc-source-trunk/gcc/emit-rtl.c:606
0x82b5ce const_vector_from_tree
        ../../gcc-source-trunk/gcc/expr.c:11531
0x82b5ce expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        ../../gcc-source-trunk/gcc/expr.c:9748
0xa65c6a expand_expr
        ../../gcc-source-trunk/gcc/expr.h:256
0xa65c6a vector_compare_rtx
        ../../gcc-source-trunk/gcc/optabs.c:5299
0xa7025d expand_vec_cond_expr(tree_node*, tree_node*, tree_node*, tree_node*,
rtx_def*)
        ../../gcc-source-trunk/gcc/optabs.c:5629
0x840c35 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        ../../gcc-source-trunk/gcc/expr.c:9358
0x7274a1 expand_gimple_stmt_1
        ../../gcc-source-trunk/gcc/cfgexpand.c:3654
0x7274a1 expand_gimple_stmt
        ../../gcc-source-trunk/gcc/cfgexpand.c:3714
0x7296ea expand_gimple_basic_block
        ../../gcc-source-trunk/gcc/cfgexpand.c:5720
0x72eafe execute
        ../../gcc-source-trunk/gcc/cfgexpand.c:6335
Please submit a full bug report,
with preprocessed source if appropriate.
gcc version 6.0.0 20160324 (experimental) [trunk revision 234448] (GCC)
$:
$: gcc-trunk -O3 small.c
small.c:4:5: warning: array âaâ assumed to have one element
 int a[];
     ^
small.c: In function âfn1â:
small.c:11:14: warning: iteration 2147483645 invokes undefined behavior
[-Waggressive-loop-optimizations]  
   for (; c; c++) {
             ~^~
small.c:11:3: note: within this loop
   for (; c; c++) {
   ^~~
small.c:7:6: internal compiler error: in immed_wide_int_const, at
emit-rtl.c:606
 void fn1() {
      ^~~
0x806f7d immed_wide_int_const(generic_wide_int<wide_int_ref_storage<false> >
const&, machine_mode)
        ../../gcc-source-trunk/gcc/emit-rtl.c:606
0x82b5ce const_vector_from_tree
        ../../gcc-source-trunk/gcc/expr.c:11531
0x82b5ce expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        ../../gcc-source-trunk/gcc/expr.c:9748
0xa65c6a expand_expr
        ../../gcc-source-trunk/gcc/expr.h:256
0xa65c6a vector_compare_rtx
        ../../gcc-source-trunk/gcc/optabs.c:5299
0xa7025d expand_vec_cond_expr(tree_node*, tree_node*, tree_node*, tree_node*,
rtx_def*)
        ../../gcc-source-trunk/gcc/optabs.c:5629
0x840c35 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        ../../gcc-source-trunk/gcc/expr.c:9358
0x7274a1 expand_gimple_stmt_1
        ../../gcc-source-trunk/gcc/cfgexpand.c:3654
0x7274a1 expand_gimple_stmt
        ../../gcc-source-trunk/gcc/cfgexpand.c:3714
0x7296ea expand_gimple_basic_block
        ../../gcc-source-trunk/gcc/cfgexpand.c:5720
0x72eafe execute
        ../../gcc-source-trunk/gcc/cfgexpand.c:6335
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.
$:
$: cat small.c
struct S2 {
  signed f1 : 3;
};
int a[];
int b, c;
char d;
void fn1() {
  struct S2 e;
  b / e.f1;
  c = 2;
  for (; c; c++) {
    d = 0;
    a[c] = ~e.f1 != d;
  }
}
$: