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--- a
+++ b/m4/single_cxx_check.m4
@@ -0,0 +1,15 @@
+dnl
+dnl AC_SINGLE_CXX_CHECK(CACHEVAR, FUNCTION, HEADER, PROGRAM)
+dnl                     $1,       $2,       $3,     $4,
+
+AC_DEFUN([AC_SINGLE_CXX_CHECK],
+[
+  AC_CACHE_CHECK([for $2 in $3], [$1],
+  [
+    AC_LANG_PUSH([C++])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include ]][$3], [$4])],
+                      [$1][[=yes]],
+                      [$1][[=no]])
+    AC_LANG_POP([C++])
+  ])
+])