Fix issues with compiling graphics/grDevices and fficall with non-gcc compilers

com.oracle.truffle.r.native/fficall/src/include/Defn.h

@@ -6,7 +6,7 @@
  * Copyright (c) 1995, 1996, 1997  Robert Gentleman and Ross Ihaka
  * Copyright (c) 1995-2014, The R Core Team
  * Copyright (c) 2002-2008, The R Foundation
- * Copyright (c) 2015, Oracle and/or its affiliates
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates
  *
  * All rights reserved.
  */
@@ -19,6 +19,7 @@
 #define HAVE_ERRNO_H 1
 
 #include <stdlib.h>
+#include <alloca.h> // Required for non gcc compilers
 #include <Rinternals.h>
 
 // various definitions required to compile GNU-R code:

com.oracle.truffle.r.native/library/grDevices/src/gzio.c

@@ -6,14 +6,16 @@
  * Copyright (c) 1995, 1996, 1997  Robert Gentleman and Ross Ihaka
  * Copyright (c) 1995-2014, The R Core Team
  * Copyright (c) 2002-2008, The R Foundation
- * Copyright (c) 2015, Oracle and/or its affiliates
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates
  *
  * All rights reserved.
  */
 
 // This simply includes gzio.h (which actually contains code)
 
+
 #define f_tell ftell
+#define f_seek fseek
 #define warning Rf_warning
 
 #include GNUR_GZIO_H