From b623eb5603c32b73b50c5f387584944f476484c6 Mon Sep 17 00:00:00 2001
From: Simon Byrne <simonbyrne@gmail.com>
Date: Mon, 12 Jul 2021 21:13:59 -0700
Subject: [PATCH] use unsafe_convert instead of cconvert to ensure handles
 aren't GCed during ccall (#482)

---
 src/handle.jl | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/handle.jl b/src/handle.jl
index c202e12b9..4efe8e2f6 100644
--- a/src/handle.jl
+++ b/src/handle.jl
@@ -32,6 +32,9 @@ macro mpi_handle(def, mpiname=nothing, extrafields...)
 
         # allows us to pass XX objects directly into MPI_XX ccall signatures
         function Base.cconvert(::Type{$mpiname}, obj::$name)
+            obj
+        end
+        function Base.unsafe_convert(::Type{$mpiname}, obj::$name)
             obj.val
         end
         # allows us to pass XX objects directly into Ptr{MPI_XX} ccall signatures