Paolo Bonzini wrote:
http://www.kb.cert.org/vuls/id/162289
The GCC SC was aware of this CERT posting before it was public. Our
feeling is that this is not a GCC bug, although it is something that we
would like GCC to warn about. I talked to Ian Taylor and he agreed to
work on the warning.
Some other compilers do this optimization too, so compiling similar
applications with them will also lead to the removal of the test. We've
identified one specific highly-optimizing compiler that does this
optimization. If you have information about other such compilers,
please send it to me, and I will forward to CERT. We would like to
counter the idea that GCC is unique in this regard. (In fact, I expect
that the reason that this issue was found with GCC is that GCC is used
so widely!)
Here is the test program:
int f(char *buf, int len) {
len = 1 << 30;
if (buf + len < buf)
return 1;
return 0;
}
If you know of a non-GCC compiler that optimizes away the test (so that
the function always returns 0), please post here, and let me know the
name, version number, command-line options, etc. you used to demonstrate
that.
Thanks,
--
Mark Mitchell
CodeSourcery
[EMAIL PROTECTED]
(650) 331-3385 x713
