Added --disable-tr1-headers switch which prevents checking for TR1

headers tuple, array, type_traits.

This is needed because xlc otherwise finds the tr1 headers of gcc and
later on is not smart enough to understand and compile them.

[[Imported from SVN: r5344]]

m4/dune_common.m4

@@ -37,7 +37,17 @@ AC_DEFUN([DUNE_COMMON_CHECKS],
   dnl checks for header files.
   AC_REQUIRE([AC_HEADER_STDC])
   AC_LANG_PUSH([C++])
-  AC_CHECK_HEADERS([malloc.h string.h type_traits tr1/type_traits array tr1/array tuple tr1/tuple])
+  # Allow disabling tr1 headers. E.g. needed for broken xlc on Blue Gene
+  AC_ARG_ENABLE(tr1-headers, 
+	AC_HELP_STRING([--disable-tr1-headers], 
+	[Prevents checking for  tr1 headers like tuple, array, etc. 
+	This might be needed for broken compilers like xlc on Blue Gene]), 
+	[], [enable_tr1_headers=yes])
+
+  if test "x$enable_tr1_headers" = "xyes" ; then
+    tr1_headers="type_traits tr1/type_traits array tr1/array tuple tr1/tuple"
+  fi
+  AC_CHECK_HEADERS([malloc.h string.h $tr1_headers])
   AC_LANG_POP([C++])
 
   dnl checks for typedefs, structures, and compiler characteristics.