From 9755bcbdab9bd6813d914915ef3887b78166f845 Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@univ-fcomte.fr>
Date: Fri, 20 Dec 2019 23:57:22 +0100
Subject: [PATCH] Ensure malloc is not called with a size of 0.

---
 src/smpi/mpi/smpi_comm.cpp | 1 +
 src/smpi/mpi/smpi_win.cpp  | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/smpi/mpi/smpi_comm.cpp b/src/smpi/mpi/smpi_comm.cpp
index 5248ee9b17..e4e9929a0b 100644
--- a/src/smpi/mpi/smpi_comm.cpp
+++ b/src/smpi/mpi/smpi_comm.cpp
@@ -424,6 +424,7 @@ void Comm::init_smp(){
       leader_group_size++;
     }
   }
+  xbt_assert(leader_group_size > 0);
   std::sort(leader_list, leader_list + leader_group_size);
 
   MPI_Group leaders_group = new  Group(leader_group_size);
diff --git a/src/smpi/mpi/smpi_win.cpp b/src/smpi/mpi/smpi_win.cpp
index 4d74e826f9..c7450299fe 100644
--- a/src/smpi/mpi/smpi_win.cpp
+++ b/src/smpi/mpi/smpi_win.cpp
@@ -735,7 +735,7 @@ int Win::shared_query(int rank, MPI_Aint* size, int* disp_unit, void* baseptr)
     *static_cast<void**>(baseptr) = target_win->base_;
   } else {
     *size                         = 0;
-    *static_cast<void**>(baseptr) = xbt_malloc(0);
+    *static_cast<void**>(baseptr) = nullptr;
   }
   return MPI_SUCCESS;
 }
-- 
2.20.1