From 22f5e5fd3e7f4cf15c38c2b3be0b0e357854026a Mon Sep 17 00:00:00 2001
From: tgschultz <tgschultz@gmail.com>
Date: Sat, 20 Apr 2019 17:24:40 +0000
Subject: [PATCH] Fixes DirectAllocator Windows implementation to call HeapFree
 when new_size == 0

---
 std/heap.zig | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/std/heap.zig b/std/heap.zig
index 472bf5e523..143429eea1 100644
--- a/std/heap.zig
+++ b/std/heap.zig
@@ -151,6 +151,13 @@ pub const DirectAllocator = struct {
                 const old_record_addr = old_adjusted_addr + old_mem.len;
                 const root_addr = @intToPtr(*align(1) usize, old_record_addr).*;
                 const old_ptr = @intToPtr(*c_void, root_addr);
+                
+                if(new_size == 0)
+                {
+                    if(os.windows.HeapFree(self.heap_handle.?, 0, old_ptr) == 0) unreachable;
+                    return old_mem[0..0];
+                }
+                
                 const amt = new_size + new_align + @sizeOf(usize);
                 const new_ptr = os.windows.HeapReAlloc(
                     self.heap_handle.?,