diff --git a/Mac/mwerks/mwerksglue.c b/Mac/mwerks/mwerksglue.c
index ae6c1ff..82f59d9 100644
--- a/Mac/mwerks/mwerksglue.c
+++ b/Mac/mwerks/mwerksglue.c
@@ -8,9 +8,131 @@
 #include <Files.h>
 #include <Strings.h>
 
+#include <stdlib.h>
 #include <stdio.h>
 #include <errno.h>
 
+/* #define DBGMALLOC /**/
+
+#ifdef DBGMALLOC
+#define NMALLOC 50000
+static long m_index;
+static long m_addrs[NMALLOC];
+static long m_sizes[NMALLOC];
+static long m_lastaddr;
+
+#define SSLOP 2
+#define SLOP (SSLOP+0)
+
+void
+m_abort() {
+	printf("ABORT\n");
+	exit(1);
+}
+
+void *
+checkrv(ptr, size)
+	void *ptr;
+	int size;
+{
+	long b = (long)ptr, e = (long)ptr + size+SSLOP;
+	int i;
+	
+	if ( m_index >= NMALLOC ) {
+		printf("too many mallocs\n");
+		m_abort();
+	}
+	m_lastaddr = (long)ptr;
+	for(i=0; i<m_index; i++) {
+		if ( m_addrs[i] > 0 && b < m_addrs[i]+m_sizes[i] && e > m_addrs[i] ) {
+			printf("overlapping block with %d\n", i);
+			m_abort();
+		}
+	}
+	m_sizes[m_index] = size;
+	m_addrs[m_index++] = (long)ptr;
+	*(short *)ptr = m_index-1;
+	return (void *)((char *)ptr+SSLOP);
+	
+}
+
+void *
+checkfree(ptr)
+	void *ptr;
+{
+	int i;
+	
+	if ( ptr == 0 ) {
+		printf("free null\n");
+		m_abort();
+	}
+	m_lastaddr = (long)ptr;
+	for(i=0; i<m_index; i++) {
+		if ( m_addrs[i] == (long)ptr-SSLOP ) {
+			m_addrs[i] = -m_addrs[i];
+			ptr = (void *)((char *)ptr-SSLOP);
+			if ( *(short *)ptr != i ) {
+				int saved_i = i, saved_ptr = *(short *)ptr;
+				
+				printf("Wrong starter value\n");
+				m_abort();
+			}
+			return ptr;
+		}
+	}
+	printf("free unknown\n");
+	m_abort();
+	return 0;
+}
+
+void *
+m_malloc(size)
+{
+	void *ptr;
+	
+	ptr = malloc(size+SLOP);
+	if ( !ptr ) {
+		printf("malloc failure\n");
+		m_abort();
+	}
+	return checkrv(ptr, size);
+}
+
+void *
+m_realloc(optr, size)
+	void *optr;
+{
+	void *ptr;
+	
+	ptr = checkfree(ptr);
+	ptr = realloc(ptr, size+SLOP);
+	if ( !ptr ) {
+		printf("realloc failure\n");
+		m_abort();
+	}
+	return checkrv(ptr, size);
+}
+
+void *
+m_calloc(size, nelem)
+{
+	void *ptr;
+	
+	ptr = calloc(1, nelem*size+SLOP);
+	return checkrv(ptr, nelem*size);
+}
+
+void
+m_free(ptr)
+	void *ptr;
+{
+	
+	ptr = checkfree(ptr);
+	free(ptr);
+}
+#endif /* DBGMALLOC */
+
+#ifdef CW4
 int
 fileno(fp)
 	FILE *fp;
@@ -39,5 +161,6 @@
 	errno= err;
 	return -1;
 }
+#endif /* CW4 */
 
 #endif /* __MWERKS__ */
\ No newline at end of file