nearest_neighbor_graph: cast the result of calls to 'malloc'

This pre-emptively suppresses some `-fpermissive` warnings when transitioning
this code to C++ in an upcoming commit.

Gitlab: #2154

diff --git a/lib/mingle/nearest_neighbor_graph.c b/lib/mingle/nearest_neighbor_graph.c
index 1de680376dc0f3c82ef1e0bfd91520ad6738eb25..b74e3dbdfe5773dfd6ca7fd1e25b3e39212cc2d1 100644 (file)
--- a/lib/mingle/nearest_neighbor_graph.c
+++ b/lib/mingle/nearest_neighbor_graph.c
@@ -32,9 +32,9 @@ SparseMatrix nearest_neighbor_graph(int nPts, int num_neigbors, double *x, doubl
   int k = num_neigbors;
 
   /* need to *2 as we do two sweeps of neighbors, so could have repeats */
-  irn =  MALLOC(sizeof(int)*nPts*k*2);
-  jcn =  MALLOC(sizeof(int)*nPts*k*2);
-  val =  MALLOC(sizeof(double)*nPts*k*2);
+  irn =  (int*)MALLOC(sizeof(int)*nPts*k*2);
+  jcn =  (int*)MALLOC(sizeof(int)*nPts*k*2);
+  val =  (double*)MALLOC(sizeof(double)*nPts*k*2);
 
 #ifdef HAVE_ANN
   nearest_neighbor_graph_ann(nPts, num_neigbors, eps, x, &nz, &irn, &jcn, &val);