[Rd] eval(match.call()) (PR#9339)

[marc_schwartz at comcast.net]

On Fri, 2006-11-03 at 14:14 -0800, Bill Dunlap wrote:
> On Fri, 3 Nov 2006 marc_schwartz at comcast.net wrote:
> 
> > > > On Fri, 2006-11-03 at 21:15 +0100, Peter Dalgaard wrote:
> > > > > > x <- quote(match.call())
> > > > > > eval(x)
> > > > > *** buffer overflow detected ***: /usr/lib/R/bin/exec/R terminated
> > > > > /lib/libc.so.6(__chk_fail+0x41)[0x1f1161]
> > > > > /lib/libc.so.6[0x1f0617]
> >
> > > > > does look like something that just Should Not Happen...
> 
> 
> I think valgrind shows the problem is in deparse.c:
>     245         strncpy(data, CHAR(STRING_ELT(svec, 0)), 10);
>     246         if (strlen(CHAR(STRING_ELT(svec, 0))) > 10) strcat(data, "...");
> You need to put a '\0' into data[10] after that strncpy
> so strcat can find the end of the string when the length
> of the copied string is >=10.  It currently runs into
> uninitialized memory at the end of ".Primitive".
> 
> (This is in a copy of R source from June 2006.)

The code is the same, but a couple of lines off in my copy from R 2.4.0
patched.

Now lines 247 and 248.

Thanks Bill. This would help to explain the difference in behaviors
observed.

Regards,

Marc