Am Freitag, dem 24.02.2023 um 03:01 +0000 schrieb Peter Lafreniere: ... > > > Maybe it could do an exception for printing, that is, reading a pointer > > is not a problem in itself, a long as you don't compare it, but I'm not > > such an expert about this. > > One last thought: with the above strict interpretation of the c standard, > it would become nigh on impossible to implement the malloc(3) family of > functions in c themselves. I vote for the "shared storage" interpretation > of the c11 standard that is actually implemented rather than this abstract > liveness oriented interpretation.
This is a bit of a misunderstanding about what "undefined behavior" means in ISO C. It simply means that ISO C does not specify the behavior. This does not mean it is illegal to do something which has undefined behavior. Instead, it means you can not rely on the ISO C standard for portable behavior. So if you implement "malloc" in C itself you will probably rely on "undefined behavior", but this is perfectly fine. The C standard specifies behavior of "malloc", but does not care how it is implemented. Martin
