[PATCH] Fix ICE on invalid with -Walloca-larger-than (PR tree-optimization/80109)

[Marek Polacek]

We crash with this invalid testcase because we aren't properly checking what we
are passing down to get_range_info, i.e., we can't pass a pointer.  So fixed by
checking the argument first, and calling alloca_type_and_limit if it is of a
wrong type.

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2017-03-20  Marek Polacek  <pola...@redhat.com>
            Martin Sebor  <mse...@redhat.com>

        PR tree-optimization/80109
        * gimple-ssa-warn-alloca.c (alloca_call_type): Only call get_range_info
        on INTEGRAL_TYPE_P.

        * gcc.dg/Walloca-14.c: New test.

diff --git gcc/gimple-ssa-warn-alloca.c gcc/gimple-ssa-warn-alloca.c
index b940efa..ec95cc6 100644
--- gcc/gimple-ssa-warn-alloca.c
+++ gcc/gimple-ssa-warn-alloca.c
@@ -327,11 +327,20 @@ alloca_call_type (gimple *stmt, bool is_vla, tree 
*invalid_casted_type)
              // away with better range information.  But it gets
              // most of the cases.
              gimple *def = SSA_NAME_DEF_STMT (len);
-             if (gimple_assign_cast_p (def)
-                 && TYPE_UNSIGNED (TREE_TYPE (gimple_assign_rhs1 (def))))
+             if (gimple_assign_cast_p (def))
                {
-                 len_casted = gimple_assign_rhs1 (def);
-                 range_type = get_range_info (len_casted, &min, &max);
+                 tree rhs1 = gimple_assign_rhs1 (def);
+                 tree rhs1type = TREE_TYPE (rhs1);
+
+                 // Bail if the argument type is not valid.
+                 if (!INTEGRAL_TYPE_P (rhs1type))
+                   return alloca_type_and_limit (ALLOCA_OK);
+
+                 if (TYPE_UNSIGNED (rhs1type))
+                   {
+                     len_casted = rhs1;
+                     range_type = get_range_info (len_casted, &min, &max);
+                   }
                }
              // An unknown range or a range of the entire domain is
              // really no range at all.
diff --git gcc/testsuite/gcc.dg/Walloca-14.c gcc/testsuite/gcc.dg/Walloca-14.c
index e69de29..6ff2e7f 100644
--- gcc/testsuite/gcc.dg/Walloca-14.c
+++ gcc/testsuite/gcc.dg/Walloca-14.c
@@ -0,0 +1,12 @@
+/* PR tree-optimization/80109 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -Walloca-larger-than=126812070" } */
+
+void
+g (int *p)
+{
+  extern void f (void *);
+
+  void *q = __builtin_alloca (p); /* { dg-warning "passing argument 1" } */
+  f (q);
+}

        Marek