Bug? Predefined Processor ID Macros in gcc 3.3

[Scott Robert Ladd]

It appears that predefined macros have changed between 3.2 and 3.3. 
Compiling with the -march=pentium3 flag with gcc 3.2.x defines the 
macros __pentium3 and __pentium3__. Under the 2003-04-21 snapshot of 
3.3, compiling with -march=pentium3 replaces these macros with 
__tune_pentium3__.

Is this an intentional change, or should I report it as a bug?

What is the sanctioned technique for determining the processor selected 
for a given compilation?

-- 
Scott Robert Ladd
Coyote Gulch Productions (http://www.coyotegulch.com)