Strange warning behavior with gcc and signed/unsigned comparisons

Question

I have the following code :

unsigned int a;
if (a > numeric_limits<int>::max())
   do_stuff();

When compiling, gcc complains about

warning: "comparison between signed and unsigned"

OK, I understand

But, with the following code :

unsigned int a;
if (a > (numeric_limits<int>::max()))
   do_stuff();

The warning is no longer displayed and I really don't know why... Is there any logical reason for such a behavior or am I doing something wrong?!

Answer 1

It's because it is a bug. See bug 50012