[2831] detect buildability of managed_mapped_file, w/ or w/o -Werror.

m4macros/ax_boost_for_bind10.m4

@@ -23,7 +23,11 @@ dnl   BOOST_OFFSET_PTR_WOULDFAIL set to "yes" if offset_ptr would cause build
 dnl                              error; otherwise set to "no"
 dnl   BOOST_NUMERIC_CAST_WOULDFAIL set to "yes" if numeric_cast would cause
 dnl                                build error; otherwise set to "no"
-dnl
+dnl   BOOST_MAPPED_FILE_WOULDFAIL set to "yes" if managed_mapped_file would
+dnl                               cause build failure; otherwise set to "no"
+dnl   BOOST_MAPPED_FILE_CXXFLAG set to the compiler flag that would need to
+dnl                             compile managed_mapped_file (can be empty).
+dnl                             It is of no use if "WOULDFAIL" is yes.
 
 AC_DEFUN([AX_BOOST_FOR_BIND10], [
 AC_LANG_SAVE
@@ -101,9 +105,49 @@ if test "X$GXX" = "Xyes"; then
 
    CXXFLAGS="$CXXFLAGS_SAVED"
 else
-  # This doesn't matter for non-g++
-  BOOST_NUMERIC_CAST_WOULDFAIL=no
+   # This doesn't matter for non-g++
+
+   CXXFLAGS="$CXXFLAGS_SAVED"
+fi
+
+# Boost interprocess::managed_mapped_file is highly system dependent and
+# can cause many portability issues.  We are going to check if it could
+# compile at all, possibly with being lenient about compiler warnings.
+BOOST_MAPPED_FILE_WOULDFAIL=yes
+BOOST_MAPPED_FILE_CXXFLAG=
+CXXFLAGS_SAVED="$CXXFLAGS"
+try_flags="no"
+if test "X$GXX" = "Xyes"; then
+  CXXFLAGS="$CXXFLAGS -Werror"
+  try_flags="$try_flags -Wno-error"
 fi
+# clang can cause false positives with -Werror without -Qunused-arguments
+AC_CHECK_DECL([__clang__], [CXXFLAGS="$CXXFLAGS -Qunused-arguments"], [])
+
+AC_MSG_CHECKING([Boost managed_mapped_file compiles])
+CXXFLAGS_SAVED2="$CXXFLAGS"
+for flag in $try_flags; do
+  if test "$flag" != no; then
+    BOOST_MAPPED_FILE_CXXFLAG="$flag"
+  fi
+  CXXFLAGS="$CXXFLAGS $BOOST_MAPPED_FILE_CXXFLAG"
+  AC_TRY_COMPILE([
+  #include <boost/interprocess/managed_mapped_file.hpp>
+  ],[
+  return (boost::interprocess::managed_mapped_file().all_memory_deallocated());
+  ],[AC_MSG_RESULT([yes, with $flag flag])
+     BOOST_MAPPED_FILE_WOULDFAIL=no
+     break
+  ],[])
+
+  CXXFLAGS="$CXXFLAGS_SAVED2"
+done
+
+if test $BOOST_MAPPED_FILE_WOULDFAIL = yes; then
+  AC_MSG_RESULT(no)
+fi
+
+CXXFLAGS="$CXXFLAGS_SAVED"
 
 AC_SUBST(BOOST_INCLUDES)