[Bug tree-optimization/96967] [11 Regression] ICE in decompose, at wide-int.h:984

[aldyh at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96967

Aldy Hernandez <aldyh at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2020-09-08
     Ever confirmed|0                           |1

--- Comment #1 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
Confirmed.

This is the same issue as PR96818.  It's another intersect that's missing a
cast.  Testing the following patch:

diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index f7b0692..b493e40 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -3828,6 +3828,8 @@ find_case_label_range (gswitch *switch_stmt, const irange
*range_of_op)
       tree case_high
        = CASE_HIGH (label) ? CASE_HIGH (label) : CASE_LOW (label);
       int_range_max label_range (CASE_LOW (label), case_high);
+      if (!types_compatible_p (label_range.type (), range_of_op->type ()))
+       range_cast (label_range, range_of_op->type ());
       label_range.intersect (range_of_op);
       if (label_range == *range_of_op)
        return label;