diff --git a/Geo/GModelIO_Mesh.cpp b/Geo/GModelIO_Mesh.cpp
index e3e1e33b06d819ad603ee4e3fd8eb95d993f7c6a..7a53dd3f0a7e69c346d6b26f3e031485f776193d 100644
--- a/Geo/GModelIO_Mesh.cpp
+++ b/Geo/GModelIO_Mesh.cpp
@@ -29,7 +29,7 @@
 #include "discreteFace.h"
 #include "discreteRegion.h"
 #include "MVertexPositionSet.h"
-#include "Os.h"
+#include "OS.h"
 
 #if defined(HAVE_POST)
 #include "PView.h"
diff --git a/Mesh/meshGFaceOptimize.cpp b/Mesh/meshGFaceOptimize.cpp
index 919b53e09ce5cd4cdaae5a6268e8df8a5c632378..d63ae2523293fcf3f456fc6eb6b4e1a00512bb01 100644
--- a/Mesh/meshGFaceOptimize.cpp
+++ b/Mesh/meshGFaceOptimize.cpp
@@ -17,7 +17,7 @@
 #include "GmshMessage.h"
 #include "Generator.h"
 #include "Context.h"
-#include "Os.h"
+#include "OS.h"
 
 #ifdef HAVE_MATCH
 extern "C" int FAILED_NODE;