diff --git a/Fltk/onelabWindow.cpp b/Fltk/onelabWindow.cpp
index 0bb535d8499b4d0ba18e2b1b38c2e99c6affade3..aea754fa602a136dabe20613e70bde9ff9b3f2a8 100644
--- a/Fltk/onelabWindow.cpp
+++ b/Fltk/onelabWindow.cpp
@@ -288,7 +288,7 @@ bool onelab::localNetworkClient::run()
       break;
     case GmshSocket::GMSH_MERGE_FILE:
       if(FlGui::instance()->onelab->mergeAuto()){
-        int n = PView::list.size();
+        unsigned int n = PView::list.size();
         MergePostProcessingFile(message, FlGui::instance()->onelab->showLastStep(),
                                 FlGui::instance()->onelab->hideNewViews(), true);
         drawContext::global()->draw();