From: Andrew MacLeod <amacleod@redhat.com>
Date: Tue, 6 Oct 2020 20:52:03 +0000 (-0400)
Subject: Off by one final fix.
X-Git-Tag: upstream/12.2.0~13251
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4e9213027587b807ca7e4bbde706b19102342d37;p=platform%2Fupstream%2Fgcc.git

Off by one final fix.

Allocate the memory in an approved portable way.

gcc/ChangeLog:

2020-10-06  Andrew MacLeod  <amacleod@redhat.com>

	* value-range.h (irange_allocator::allocate): Allocate in two hunks
	instead of using the variably-sized trailing array approach.
---

diff --git a/gcc/value-range.h b/gcc/value-range.h
index 7031a82..63c9620 100644
--- a/gcc/value-range.h
+++ b/gcc/value-range.h
@@ -668,13 +668,12 @@ irange_allocator::allocate (unsigned num_pairs)
   if (num_pairs < 2)
     num_pairs = 2;
 
-  struct newir {
-    irange range;
-    tree mem[2];
-  };
-  size_t nbytes = (sizeof (newir) + sizeof (tree) * 2 * (num_pairs - 1));
-  struct newir *r = (newir *) obstack_alloc (&m_obstack, nbytes);
-  return new (r) irange (r->mem, num_pairs);
+  size_t nbytes = sizeof (tree) * 2 * num_pairs;
+
+  // Allocate the irange and required memory for the vector.
+  void *r = obstack_alloc (&m_obstack, sizeof (irange));
+  tree *mem = (tree *) obstack_alloc (&m_obstack, nbytes);
+  return new (r) irange (mem, num_pairs);
 }
 
 inline irange *