I'm not sure that I understand what the infringement is either.
As I understand it, CISCO can only have infringed the GPL if they have modified any of the GPL'd code, and put it in a product without making the changes they made to the source available. If this is the case, all they need to do is to provide, on request, the altered code to whoever asks for it. They do not even have to put it on a publicly accessible web site.
There is certainly no block on USING, say the GCC compiler, libraries and other tools to create a commercial product which is NOT covered by the GPL, provided that no modified code licensed under the GPL is included in the product. If this were not the case, then any software developed using GPL'd tools would have to be published under the GPL, a situation that is explained at some length in the information about the GNU Public License.
Linking against the libraries is allowed, but modifying the libraries, compiler or tools to produce the product without making the source changes available is not. I would assume that the process of porting to a new architecture which required library or compiler changes would require those changes to be made available.
I would expect that if the libraries were modified as part of the porting process to produce the product, then these changes would have to be published, although it may be a moot point as to whether using a modified compiler counts as included code. It would certainly be against the spirit of the GPL, but it may not break the license in the strictest sense. This one is probably for the lawyers.
Just my two-pennies worth, which btw. can be found in the right pocket.