This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Optimization of conditional access to globals: thread-unsafe?


Darryl Miles wrote:

This then leads into the question. Is a pointer allowed to be invalid.

I'm sure I have read a comment on this before, along the line of the spec says it must be valid or a certain number of other values (like zero or one past being valid). But I can not cite chapter and verse if this is true.

Well most certainly it can be null, and the code sequence in question could just be testing a pointer for being null, that's certainly very common code, and in fact I don't see why this won't cause trouble???


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]