Block sigint in allocations

[drmeister]

[rptb1]

Just a note to say that calling sigprocmask is expensive and there's no way you want to do it around allocations in general.

[rptb1]

There are ways to prevent signals causing re-entry without actually making the system call to sigprocmask. I'm not sure what your motivation is, so I can't comment on why you need this. However, take a look at http://locklessinc.com/articles/signalsafe_locks/