[PATCH] Don't ICE with huge alignment (PR middle-end/60226)

[Marek Polacek]

This should fix ICE on insane alignment.  Normally, check_user_alignment
detects e.g. alignment 1 << 32, but not 1 << 28.  However, record_align
is in bits, so it's actually 8 * (1 << 28) and that's greater than
INT_MAX.  This patch rejects such code.

In the middle hunk, we should give up when an error occurs, we don't
want to call finalize_type_size in that case -- we'd ICE in there.

Regtested/bootstrapped on x86_64-linux, ok for trunk?

2014-03-04  Marek Polacek  <pola...@redhat.com>

        PR middle-end/60226
        * stor-layout.c (layout_type): Return if alignment of array elements
        is greater than element size.  Error out if requested alignment is too
        large.
cp/
        * class.c (layout_class_type): Error out if requested alignment is too
        large.
testsuite/
        * c-c++-common/pr60226.c: New test.

diff --git gcc/cp/class.c gcc/cp/class.c
index b46391b..e6325b3 100644
--- gcc/cp/class.c
+++ gcc/cp/class.c
@@ -6378,6 +6378,14 @@ layout_class_type (tree t, tree *virtuals_p)
   if (TYPE_PACKED (t) && !layout_pod_type_p (t))
     rli->packed_maybe_necessary = true;
 
+  if (rli->record_align >= (1U << (HOST_BITS_PER_INT - 1)))
+    {
+      TYPE_SIZE (rli->t) = integer_zero_node;
+      TYPE_SIZE_UNIT (rli->t) = integer_zero_node;
+      error ("requested alignment is too large");
+      return;
+    }
+
   /* Let the back end lay out the type.  */
   finish_record_layout (rli, /*free_p=*/true);
 
diff --git gcc/stor-layout.c gcc/stor-layout.c
index 084d195..445f0d5 100644
--- gcc/stor-layout.c
+++ gcc/stor-layout.c
@@ -2266,8 +2266,11 @@ layout_type (tree type)
            && !TREE_OVERFLOW (TYPE_SIZE_UNIT (element))
            && !integer_zerop (TYPE_SIZE_UNIT (element))
            && compare_tree_int (TYPE_SIZE_UNIT (element),
-                                TYPE_ALIGN_UNIT (element)) < 0)
-         error ("alignment of array elements is greater than element size");
+                                TYPE_ALIGN_UNIT (element)) < 0)
+         {
+           error ("alignment of array elements is greater than element size");
+           return;
+         }
        break;
       }
 
@@ -2294,6 +2297,14 @@ layout_type (tree type)
        if (TREE_CODE (type) == QUAL_UNION_TYPE)
          TYPE_FIELDS (type) = nreverse (TYPE_FIELDS (type));
 
+       if (rli->record_align >= (1U << (HOST_BITS_PER_INT - 1)))
+         {
+           TYPE_SIZE (rli->t) = integer_zero_node;
+           TYPE_SIZE_UNIT (rli->t) = integer_zero_node;
+           error ("requested alignment is too large");
+           return;
+         }
+
        /* Finish laying out the record.  */
        finish_record_layout (rli, /*free_p=*/true);
       }
diff --git gcc/testsuite/c-c++-common/pr60226.c 
gcc/testsuite/c-c++-common/pr60226.c
index e69de29..0d7d74d 100644
--- gcc/testsuite/c-c++-common/pr60226.c
+++ gcc/testsuite/c-c++-common/pr60226.c
@@ -0,0 +1,12 @@
+/* PR c/60226 */
+/* { dg-do compile } */
+/* { dg-options "-Wno-c++-compat" { target c } } */
+
+typedef int __attribute__ ((aligned (1 << 28))) int28;
+int28 foo[4] = {}; /* { dg-error "alignment of array elements is greater than 
element size" } */
+
+void
+f (void)
+{
+  struct { __attribute__((aligned (1 << 28))) double a; } x; /* { dg-error 
"requested alignment is too large" } */
+}

        Marek