[buildsystem] Check for range-based for.

cmake/modules/CheckCXX11Features.cmake

@@ -10,6 +10,7 @@
 # HAVE_INTEGRAL_CONSTANT           True if compiler supports integral_constant
 # HAVE_CONSTEXPR                   True if constexpr is supported
 # HAVE_KEYWORD_FINAL               True if final is supported.
+# HAVE_RANGE_BASED_FOR             True if range-based for is supported and working.
 
 include(CMakePushCheckState)
 cmake_push_check_state()
@@ -214,4 +215,15 @@ check_cxx_source_compiles("
 " HAVE_KEYWORD_FINAL
 )
 
+# range-based for
+check_cxx_source_compiles("
+  int main(void)
+  {
+    int arr[3];
+    for(int &val : arr)
+      val = 0;
+  }
+" HAVE_RANGE_BASED_FOR
+)
+
 cmake_pop_check_state()

m4/CMakeLists.txt

@@ -11,6 +11,7 @@ install(PROGRAMS
         cxx0x_nullptr.m4
         cxx11_constexpr.m4
         cxx11_final.m4
+        cxx11_range_based_for.m4
         dune.m4
         dune_all.m4
         dune_autobuild.m4

m4/Makefile.am

@@ -14,6 +14,7 @@ ALLM4S = 					\
 	cxx0x_nullptr.m4			\
 	cxx11_constexpr.m4			\
 	cxx11_final.m4				\
+	cxx11_range_based_for.m4		\
 	dune.m4					\
 	dune_all.m4				\
 	dune_autobuild.m4			\

m4/cxx11_range_based_for.m4

+# tests for C++11 range-based for support
+# the associated define is called HAVE_RANGE_BASED_FOR
+
+AC_DEFUN([DUNE_CXX11_RANGE_BASED_FOR],[
+  AC_CACHE_CHECK([for C++11 range-based for], [dune_cv_cxx11_range_based_for_support], [
+    AC_REQUIRE([AC_PROG_CXX])
+    AC_REQUIRE([CXX11])
+    AC_LANG_PUSH([C++])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM(,[[
+          int arr[3];
+          for(int &val : arr)
+            val = 0;
+        ]])],
+      [dune_cv_cxx11_range_based_for_support=yes],
+      [dune_cv_cxx11_range_based_for_support=no])
+    AC_LANG_POP
+  ])
+  if test "x$dune_cv_cxx11_range_based_for_support" = xyes; then
+    AC_DEFINE([HAVE_RANGE_BASED_FOR], [1], [Define to 1 if C++11 range-based for is supported])
+  fi
+])

m4/dune_common.m4

@@ -21,6 +21,7 @@ AC_DEFUN([DUNE_COMMON_CHECKS],
   AC_REQUIRE([CXX11])
   AC_REQUIRE([NULLPTR_CHECK])
   AC_REQUIRE([CXX11_CONSTEXPR_CHECK])
+  AC_REQUIRE([DUNE_CXX11_RANGE_BASED_FOR])
   AC_REQUIRE([DUNE_BOOST_BASE])
   AC_REQUIRE([DUNE_LINKCXX])
   AC_REQUIRE([DUNE_CHECKDEPRECATED])