2 files changed, 38 insertions, 0 deletions
diff --git a/config/Makefile.am b/config/Makefile.am
index 535844507..ba3026cd9 100644
--- a/config/Makefile.am
+++ b/config/Makefile.am
@@ -89,6 +89,7 @@ m4macros = \
 	gr_swig.m4 \
 	gr_sysv_shm.m4 \
 	gr_version.m4 \
+	gr_vmcircbuf.m4 \
 	lf_cc.m4 \
 	lf_cxx.m4 \
 	lf_warnings.m4 \
diff --git a/config/gr_vmcircbuf.m4 b/config/gr_vmcircbuf.m4
new file mode 100644
index 000000000..cf9e394e7
--- /dev/null
+++ b/config/gr_vmcircbuf.m4
@@ -0,0 +1,37 @@
+dnl
+dnl Copyright 2011 Free Software Foundation, Inc.
+dnl 
+dnl This file is part of GNU Radio
+dnl 
+dnl GNU Radio is free software; you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 3, or (at your option)
+dnl any later version.
+dnl 
+dnl GNU Radio is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+dnl GNU General Public License for more details.
+dnl 
+dnl You should have received a copy of the GNU General Public License
+dnl along with GNU Radio; see the file COPYING.  If not, write to
+dnl the Free Software Foundation, Inc., 51 Franklin Street,
+dnl Boston, MA 02110-1301, USA.
+dnl 
+
+AC_DEFUN([GR_VMCIRCBUF],[
+  dnl Control availability of vmcircbuf methods.
+  dnl For now, only allows disabling of shm methods, which cause uncatchable
+  dnl   segmentation faults on Cygwin with gcc 4.x (x <= 5)
+
+  AC_MSG_CHECKING([whether to try shm vmcircbuf methods])
+  AC_ARG_WITH(shm-vmcircbuf,
+              [AS_HELP_STRING([--without-shm-vmcircbuf],
+                              [do not attempt to use shm vmcircbuf methods])],
+              [], [ with_shm_vmcircbuf=yes ])
+  AC_MSG_RESULT($with_shm_vmcircbuf)
+  
+  AS_IF([test "x$with_shm_vmcircbuf" != xno],
+    [AC_DEFINE([TRY_SHM_VMCIRCBUF], [1],
+               [Define if ok to try shm vmcircbuf methods]) ])
+])