Fair enough. My current solution is adequate for our purposes, as (like you said) this isn't a very common operation to perform.... That said, do you see any obvious issues with my solution? It seems to work for all of the test cases I've thrown at it, but I could be missing something. Additionally, do you have any suggestions for a better method that achieves similar results? Ideally I'd like a solution that didn't require the use of the 'optimize' attribute as (unfortunately) some of the systems on which we'd like to compile our code still use gcc < 4.4. Kevin On Wed, Aug 31, 2011 at 10:00 PM, Ian Lance Taylor <iant@xxxxxxxxxx> wrote: > Kevin Klues <klueska@xxxxxxxxxxxxxxx> writes: > >> Specifically, I want to be able to change the value of my TLS >> descriptor as well as access TLS variables from that new descriptor >> within the body of a single function. > > As you've discovered, gcc does not support that. It seems like a highly > unusual feature to want. It would not be hard to change gcc to add an > option to support this, but I'm not sure it's worth the ongoing > maintenance cost. > > Ian >