1 files changed, 40 insertions, 0 deletions
diff --git a/config/gr_check_memalign.m4 b/config/gr_check_memalign.m4
new file mode 100644
index 000000000..37ff5b795
--- /dev/null
+++ b/config/gr_check_memalign.m4
@@ -0,0 +1,40 @@
+# Copyright 2008 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Boston, MA
+# 02110-1301, USA.
+
+AC_DEFUN([GR_CHECK_MEMALIGN],
+[
+  # Check for allocing memory alignment functions
+  # If 'posix_memalign' is available, use it solely.
+  AC_CHECK_FUNCS([posix_memalign],,[
+    # Otherwise, check for valloc and the
+    # (a-priori known) alignment of 'malloc'
+    AC_CHECK_FUNCS([valloc])
+    aligned_malloc=0
+    # 'malloc' is 16-byte aligned on (at least) Darwin 8 and 9
+    case "$host_os" in
+      darwin8*) aligned_malloc=16 ;;
+      darwin9*) aligned_malloc=16 ;;
+      *) ;;
+    esac
+    if test $aligned_malloc = 0; then
+      AC_MSG_RESULT([malloc has unknown alignment.])
+    else
+      AC_MSG_RESULT([malloc is $aligned_malloc-byte aligned.])
+    fi
+    AC_DEFINE_UNQUOTED([ALIGNED_MALLOC],[$aligned_malloc],[Define as the alignment of malloc if known; otherwise 0.])
+  ])
+])