--- a/liboctave/oct-locbuf.cc	Fri Dec 02 20:33:42 2011 -0500
+++ b/liboctave/oct-locbuf.cc	Sat Dec 03 03:30:27 2011 -0500
@@ -25,44 +25,55 @@
 #endif
 
 #include <iostream>
+
+#include "lo-error.h"
 #include "oct-locbuf.h"
 
-// Query for configured chunk size, and if not defined, set it to 32 MB.
-// FIXME: 32MB is hard-coded. Maybe we could use something better, like
-// querying for available physical memory.
+// FIXME -- Maybe we should querying for available physical memory?
+
 #ifndef OCTAVE_LOCBUF_CHUNKSIZE_MB
 #define OCTAVE_LOCBUF_CHUNKSIZE_MB 32
 #endif
 
 // Each chunk will be at least this big.
+
 const size_t octave_chunk_buffer::chunk_size =
   static_cast<size_t> (OCTAVE_LOCBUF_CHUNKSIZE_MB) << 20;
 
-char *octave_chunk_buffer::top = 0, *octave_chunk_buffer::chunk = 0;
+char *octave_chunk_buffer::top = 0;
+char *octave_chunk_buffer::chunk = 0;
 size_t octave_chunk_buffer::left = 0;
+size_t octave_chunk_buffer::active = 0;
 
 octave_chunk_buffer::octave_chunk_buffer (size_t size) : cnk (0), dat (0)
 {
-  // Alignment mask. The size of double or long int, whichever is greater.
-  // All data will be aligned to this size. If it's not enough for a type,
-  // that type should not be declared as POD.
+  // Alignment mask. The size of double or long int, whichever is
+  // greater.  All data will be aligned to this size.  If it's not
+  // enough for a type, that type should not be declared as POD.
+
   static const size_t align_mask = (sizeof (long) < sizeof (double)
                                     ? sizeof (double)
                                     : sizeof (long)) - 1;
 
-  if (! size) return;
+  active++;
+
+  if (! size)
+    return;
+
   // Align size. Note that size_t is unsigned, so size-1 must correctly
   // wrap around.
+
   size = ((size - 1) | align_mask) + 1;
 
   if (size > left)
     {
       // Big buffers (> 1/8 chunk) will be allocated as stand-alone and
       // won't disrupt the chain.
+
       if (size > chunk_size >> 3)
         {
-          // Use new [] to get std::bad_alloc if out of memory. Could as
-          // well be std::malloc and handle that ourselves.
+          // Use new [] to get std::bad_alloc if out of memory.
+
           dat = new char [size];
           return;
         }
@@ -73,6 +84,7 @@
     }
 
   // Now allocate memory from the chunk and update state.
+
   cnk = chunk;
   dat = top;
   left -= size;
@@ -81,24 +93,55 @@
 
 octave_chunk_buffer::~octave_chunk_buffer (void)
 {
+  active--;
+
   if (cnk == chunk)
     {
-      // Our chunk is still the active one. Just restore the state.
+      // Our chunk is still the active one.  Just restore the state.
+
       left += top - dat;
       top = dat;
     }
-  else if (! cnk)
+  else
     {
-      // We were a stand-alone buffer.
-      delete [] dat;
+      if (cnk)
+        {
+          // Responsible for deletion.
+
+          delete [] chunk;
+          chunk = cnk;
+          top = dat;
+
+          // FIXME -- the following calcuation of remaining data will
+          // only work if each chunk has the same chunk_size.
+
+          left = chunk_size - (dat - cnk);
+        }
+      else
+        {
+          // We were a stand-alone buffer.
+
+          delete [] dat;
+        }
+    }
+}
+
+// Clear the final chunk of allocated memory.
+
+void
+octave_chunk_buffer::clear (void)
+{
+  if (active == 0)
+    {
+      delete [] chunk;
+      chunk = 0;
+      top = 0;
+      left = 0;
     }
   else
     {
-      // Responsible for deletion.
-      delete [] chunk;
-      chunk = cnk;
-      top = dat;
-      // FIXME: This will only work if chunk_size is constant.
-      left = chunk_size - (dat - cnk);
+      (*current_liboctave_warning_handler)
+        ("octave_chunk_buffer::clear: %d active allocations remain!",
+         active);
     }
 }

--- a/liboctave/oct-locbuf.h	Fri Dec 02 20:33:42 2011 -0500
+++ b/liboctave/oct-locbuf.h	Sat Dec 03 03:30:27 2011 -0500
@@ -26,8 +26,9 @@
 #include <cstddef>
 #include "oct-cmplx.h"
 
-// The default local buffer simply encapsulates an *array* pointer that gets
-// delete[]d automatically. For common POD types, we provide specializations.
+// The default local buffer simply encapsulates an *array* pointer
+// that gets deleted automatically.  For common POD types, we provide
+// specializations.
 
 template <class T>
 class octave_local_buffer
@@ -50,16 +51,17 @@
   octave_local_buffer& operator = (const octave_local_buffer&);
 };
 
-// For buffers of POD types, we'll be more smart. There is one thing that
-// differentiates a local buffer from a dynamic array - the local buffers, if
-// not manipulated improperly, have a FIFO semantics, meaning that if buffer B
-// is allocated after buffer A, B *must* be deallocated before A. This is
-// *guaranteed* if you use local buffer exclusively through the
-// OCTAVE_LOCAL_BUFFER macro, because the C++ standard *mandates* explicit
-// local objects be destroyed in reverse order of declaration.
-// Therefore, we can avoid memory fragmentation by allocating fairly large
-// chunks of memory and serving local buffers from them in a stack-like manner.
-// The first returning buffer in previous chunk will be responsible for
+// For buffers of POD types, we'll be smarter.  There is one thing
+// that differentiates a local buffer from a dynamic array - the local
+// buffers, if not manipulated improperly, have a FIFO semantics,
+// meaning that if buffer B is allocated after buffer A, B *must* be
+// deallocated before A.  This is *guaranteed* if you use local buffer
+// exclusively through the OCTAVE_LOCAL_BUFFER macro, because the C++
+// standard requires that explicit local objects be destroyed in
+// reverse order of declaration.  Therefore, we can avoid memory
+// fragmentation by allocating fairly large chunks of memory and
+// serving local buffers from them in a stack-like manner.  The first
+// returning buffer in previous chunk will be responsible for
 // deallocating the chunk.
 
 class octave_chunk_buffer
@@ -72,13 +74,30 @@
 
   char *data (void) const { return dat; }
 
+  static void clear (void);
+
 private:
+
+  // The number of bytes we allocate for each large chunk of memory we
+  // manage.
   static const size_t chunk_size;
 
-  static char *top, *chunk;
+  // Pointer to the end end of the last allocation.
+  static char *top;
+
+  // Pointer to the current active chunk.
+  static char *chunk;
+
+  // The number of bytes remaining in the active chunk.
   static size_t left;
 
+  // The number of active allocations.
+  static size_t active;
+
+  // Pointer to the current chunk.
   char *cnk;
+
+  // Pointer to the beginning of the most recent allocation.
   char *dat;
 
   // No copying!
@@ -86,8 +105,8 @@
   octave_chunk_buffer& operator = (const octave_chunk_buffer&);
 };
 
-// This specializes octave_local_buffer to use the chunked buffer mechanism
-// for POD types.
+// This specializes octave_local_buffer to use the chunked buffer
+// mechanism for POD types.
 #define SPECIALIZE_POD_BUFFER(TYPE) \
 template <> \
 class octave_local_buffer<TYPE> : private octave_chunk_buffer \
@@ -143,32 +162,37 @@
   }
 };
 
-// If the compiler supports dynamic stack arrays, we can use the attached hack
-// to place small buffer arrays on the stack. It may be even faster than our
-// obstack-like optimization, but is dangerous because stack is a very limited
-// resource, so we disable it.
-#if 0 //defined (HAVE_DYNAMIC_AUTO_ARRAYS)
+// If the compiler supports dynamic stack arrays, we can use the
+// attached hack to place small buffer arrays on the stack. It may be
+// even faster than our obstack-like optimization, but is dangerous
+// because stack is a very limited resource, so we disable it.
+
+#if 0 // defined (HAVE_DYNAMIC_AUTO_ARRAYS)
 
 // Maximum buffer size (in bytes) to be placed on the stack.
 
 #define OCTAVE_LOCAL_BUFFER_MAX_STACK_SIZE 8192
 
-// If we have automatic arrays, we use an automatic array if the size is small
-// enough.  To avoid possibly evaluating `size' multiple times, we first cache
-// it.  Note that we always construct both the stack array and the
-// octave_local_buffer object, but only one of them will be nonempty.
+// If we have automatic arrays, we use an automatic array if the size
+// is small enough.  To avoid possibly evaluating `size' multiple
+// times, we first cache it.  Note that we always construct both the
+// stack array and the octave_local_buffer object, but only one of
+// them will be nonempty.
 
 #define OCTAVE_LOCAL_BUFFER(T, buf, size) \
   const size_t _bufsize_ ## buf = size; \
   const bool _lbufaut_ ## buf = _bufsize_ ## buf * sizeof (T) \
      <= OCTAVE_LOCAL_BUFFER_MAX_STACK_SIZE; \
   T _bufaut_ ## buf [_lbufaut_ ## buf ? _bufsize_ ## buf : 0]; \
-  octave_local_buffer<T> _bufheap_ ## buf (!_lbufaut_ ## buf ? _bufsize_ ## buf : 0); \
-  T *buf = _lbufaut_ ## buf ? _bufaut_ ## buf : static_cast<T *> (_bufheap_ ## buf)
+  octave_local_buffer<T> _bufheap_ ## buf \
+    (!_lbufaut_ ## buf ? _bufsize_ ## buf : 0); \
+  T *buf = _lbufaut_ ## buf \
+    ? _bufaut_ ## buf : static_cast<T *> (_bufheap_ ## buf)
 
 #else
 
-// If we don't have automatic arrays, we simply always use octave_local_buffer.
+// If we don't have automatic arrays, we simply always use
+// octave_local_buffer.
 
 #define OCTAVE_LOCAL_BUFFER(T, buf, size) \
   octave_local_buffer<T> _buffer_ ## buf (size); \
@@ -176,13 +200,14 @@
 
 #endif
 
-// Yeah overloading macros would be nice.
-// Note: we use weird variables in the for loop to avoid warnings about
-// shadowed parameters.
+// Note: we use weird variables in the for loop to avoid warnings
+// about shadowed parameters.
+
 #define OCTAVE_LOCAL_BUFFER_INIT(T, buf, size, value) \
   OCTAVE_LOCAL_BUFFER(T, buf, size); \
   for (size_t _buf_iter = 0, _buf_size = size; \
-       _buf_iter < _buf_size; _buf_iter++) buf[_buf_iter] = value
+        _buf_iter < _buf_size; _buf_iter++) \
+    buf[_buf_iter] = value
 
 #endif
 

--- a/src/toplev.cc	Fri Dec 02 20:33:42 2011 -0500
+++ b/src/toplev.cc	Sat Dec 03 03:30:27 2011 -0500
@@ -680,6 +680,8 @@
 
   SAFE_CALL (sysdep_cleanup, ())
 
+  SAFE_CALL (octave_chunk_buffer::clear, ())
+
   if (octave_exit)
     (*octave_exit) (retval == EOF ? 0 : retval);
 }
@@ -709,9 +711,13 @@
 
       if (! error_state)
         {
-          quitting_gracefully = true;
+          // Instead of simply calling exit, we simulate an interrupt
+          // with a request to exit cleanly so that no matter where the
+          // call to quit occurs, we will run the unwind_protect stack,
+          // clear the OCTAVE_LOCAL_BUFFER allocations, etc. before
+          // exiting.
 
-          // Simulate interrupt.
+          quitting_gracefully = true;
 
           octave_interrupt_state = -1;