diff --git a/Polyhedron_IO/examples/Polyhedron_IO/off_glue.cpp b/Polyhedron_IO/examples/Polyhedron_IO/off_glue.cpp
index d5a0a20e56f..0b28f374821 100644
--- a/Polyhedron_IO/examples/Polyhedron_IO/off_glue.cpp
+++ b/Polyhedron_IO/examples/Polyhedron_IO/off_glue.cpp
@@ -45,7 +45,7 @@ int main( int argc, char **argv) {
     int n = 0; // number of filenames
     char *filename[2];
     bool help = false;
-    int i = 1;
+    std::size_t i = 1;
     for ( ; i < argc; i++) { // check commandline options
         if ( strcmp( "-v", argv[i]) == 0)
             verbose = true;