diff -rupN gmsh-3.0.6-source/Common/CommandLine.cpp gmsh-3.0.6-source-new/Common/CommandLine.cpp
--- gmsh-3.0.6-source/Common/CommandLine.cpp	2017-11-04 20:27:37.000000000 +0100
+++ gmsh-3.0.6-source-new/Common/CommandLine.cpp	2017-11-05 16:49:19.468093753 +0100
@@ -20,15 +20,6 @@
 #include "CreateFile.h"
 #include "OS.h"
 
-#if defined(HAVE_FLTK)
-#include <FL/Fl.H>
-#if (FL_MAJOR_VERSION == 1) && (FL_MINOR_VERSION >= 3)
-// OK
-#else
-#error "Gmsh requires FLTK >= 1.3"
-#endif
-#endif
-
 #if defined(HAVE_PETSC)
 #include "petsc.h"
 #endif
@@ -49,6 +40,15 @@
 #include "Parser.h"
 #endif
 
+#if defined(HAVE_FLTK)
+#include <FL/Fl.H>
+#if (FL_MAJOR_VERSION == 1) && (FL_MINOR_VERSION >= 3)
+// OK
+#else
+#error "Gmsh requires FLTK >= 1.3"
+#endif
+#endif
+
 int GetGmshMajorVersion(){ return GMSH_MAJOR_VERSION; }
 int GetGmshMinorVersion(){ return GMSH_MINOR_VERSION; }
 int GetGmshPatchVersion(){ return GMSH_PATCH_VERSION; }
diff -rupN gmsh-3.0.6-source/Fltk/helpWindow.cpp gmsh-3.0.6-source-new/Fltk/helpWindow.cpp
--- gmsh-3.0.6-source/Fltk/helpWindow.cpp	2017-10-03 22:01:51.000000000 +0200
+++ gmsh-3.0.6-source-new/Fltk/helpWindow.cpp	2017-11-05 16:49:19.468093753 +0100
@@ -3,13 +3,18 @@
 // See the LICENSE.txt file for license information. Please report all
 // bugs and problems to the public mailing list <gmsh@onelab.info>.
 
+#include "GmshConfig.h"
+
+#if defined(HAVE_MED)
+#include "med.h"
+#endif
+
 #include <sstream>
 #include <algorithm>
 #include <FL/Fl_Help_View.H>
 #include <FL/Fl_Check_Button.H>
 #include <FL/Fl_Input.H>
 #include <FL/Fl_Color_Chooser.H>
-#include "GmshConfig.h"
 #include "FlGui.h"
 #include "inputValue.h"
 #include "helpWindow.h"
@@ -33,10 +38,6 @@
 #include "Standard_Version.hxx"
 #endif
 
-#if defined(HAVE_MED)
-#include "med.h"
-#endif
-
 static const char *help_link(Fl_Widget *w, const char *uri)
 {
   fl_open_uri(uri);
diff -rupN gmsh-3.0.6-source/Geo/GModelIO_MED.cpp gmsh-3.0.6-source-new/Geo/GModelIO_MED.cpp
--- gmsh-3.0.6-source/Geo/GModelIO_MED.cpp	2017-10-03 22:01:51.000000000 +0200
+++ gmsh-3.0.6-source-new/Geo/GModelIO_MED.cpp	2017-11-05 16:49:19.469093752 +0100
@@ -25,9 +25,7 @@
 #include "MPyramid.h"
 #include "discreteVertex.h"
 
-extern "C" {
 #include <med.h>
-}
 
 #if (MED_MAJOR_NUM == 3)
 // To avoid too many ifdefs below we use defines for the bits of the
diff -rupN gmsh-3.0.6-source/Post/PViewDataGModelIO.cpp gmsh-3.0.6-source-new/Post/PViewDataGModelIO.cpp
--- gmsh-3.0.6-source/Post/PViewDataGModelIO.cpp	2017-10-03 22:01:51.000000000 +0200
+++ gmsh-3.0.6-source-new/Post/PViewDataGModelIO.cpp	2017-11-05 16:49:19.469093752 +0100
@@ -361,9 +361,7 @@ void PViewDataGModel::importLists(int N[
 
 #if defined(HAVE_MED)
 
-extern "C" {
 #include <med.h>
-}
 
 #if (MED_MAJOR_NUM == 3)
 // To avoid too many ifdefs below we use defines for the bits of the