I had the first hunk of the following patch laying around, but when I updated/compiled today, it triggered a warning: virsh.c:3162: warning: format '%d' expects type 'int', but argument 6 has type 's ize_t' I've fixed it by using %lu, which is more likely to be the same width as size_t that %d, and by casting strlen's return val to the new, expected type. 2007-03-19 Jim Meyering <jim(a)meyering.net&gt; Avoid printf-style format mismatch. * src/virsh.c (vshError): Use ATTRIBUTE_FORMAT. (_vshStrdup): Use %lu (not %d) for strlen, and cast the strlen return value to "unsigned long" to match the format. Index: src/virsh.c =================================================================== RCS file: /data/cvs/libvirt/src/virsh.c,v retrieving revision 1.65 diff -u -p -r1.65 virsh.c --- src/virsh.c 19 Mar 2007 09:46:13 -0000 1.65 +++ src/virsh.c 19 Mar 2007 14:03:10 -0000 @@ -179,8 +179,8 @@ typedef struct __vshControl { static vshCmdDef commands[]; -static void vshError(vshControl * ctl, int doexit, const char *format, - ...); +static void vshError(vshControl * ctl, int doexit, const char *format, ...) + ATTRIBUTE_FORMAT(printf, 3, 4); static int vshInit(vshControl * ctl); static int vshDeinit(vshControl * ctl); static void vshUsage(vshControl * ctl, const char *cmdname); @@ -3158,8 +3158,8 @@ _vshStrdup(vshControl * ctl, const char if ((x = strdup(s))) return x; - vshError(ctl, TRUE, _("%s: %d: failed to allocate %d bytes"), - filename, line, strlen(s)); + vshError(ctl, TRUE, _("%s: %d: failed to allocate %lu bytes"), + filename, line, (unsigned long)strlen(s)); return NULL; }