--- cvs-1.11.23/src/cvs.h
+++ cvs-1.11.23/src/cvs.h
@@ -471,6 +471,8 @@ extern void check_numeric PROTO ((const char *, int, char **));
 char *getcaller PROTO ((void));
 char *time_stamp PROTO ((const char *file));
 
+extern char *xasprintf (char **ptr, const char *fmt, ...)
+	__attribute__ ((__format__ (__printf__, 2, 3)));
 void *xmalloc PROTO((size_t bytes));
 void *xrealloc PROTO((void *ptr, size_t bytes));
 void expand_string PROTO ((char **, size_t *, size_t));
--- cvs-1.11.23/src/subr.c
+++ cvs-1.11.23/src/subr.c
@@ -14,6 +14,7 @@
  */
 
 #include <assert.h>
+#include <stdarg.h>
 #include "cvs.h"
 #include "getline.h"
 
@@ -28,6 +29,19 @@
 
 extern char *getlogin ();
 
+char *
+xasprintf (char **ptr, const char *fmt, ...)
+{
+	va_list arg;
+
+	va_start (arg, fmt);
+	if (vasprintf (ptr, fmt, arg) < 0)
+		error (1, errno, "vasprintf");
+	va_end (arg);
+
+	return *ptr;
+}
+
 /*
  * malloc some data and die if it fails
  */
@@ -37,17 +51,11 @@ xmalloc (bytes)
 {
     char *cp;
 
-    /* Parts of CVS try to xmalloc zero bytes and then free it.  Some
-       systems have a malloc which returns NULL for zero byte
-       allocations but a free which can't handle NULL, so compensate. */
-    if (bytes == 0)
-	bytes = 1;
-
     cp = malloc (bytes);
     if (cp == NULL)
     {
 	char buf[80];
-	sprintf (buf, "out of memory; can not allocate %lu bytes",
+	sprintf (buf, "cannot allocate %lu bytes: out of memory",
 		 (unsigned long) bytes);
 	error (1, 0, buf);
     }
@@ -64,17 +72,12 @@ xrealloc (ptr, bytes)
     void *ptr;
     size_t bytes;
 {
-    char *cp;
-
-    if (!ptr)
-	cp = malloc (bytes);
-    else
-	cp = realloc (ptr, bytes);
+    char *cp = realloc (ptr, bytes);
 
     if (cp == NULL)
     {
 	char buf[80];
-	sprintf (buf, "out of memory; can not reallocate %lu bytes",
+	sprintf (buf, "can not reallocate %lu bytes: out of memory",
 		 (unsigned long) bytes);
 	error (1, 0, buf);
     }