[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  <polacek@redhat.com>
	    Martin Sebor  <msebor@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