> This is writing sizeof(char) (== 1 almost everywhere)
1 everywhere. sizeof's unit is "how many chars". For instance there was a cray machine that could only access 64bit words. sizeof(char) is still 1, with 64bit chars.
> zero to address zero. It is not using a NULL macro or other predefined symbol.
Here in godbolt, clang compiling C simply deletes the code in the function past and including the null pointer dereference.
https://godbolt.org/z/9aqWPazsP
> This is writing sizeof(char) (== 1 almost everywhere)
1 everywhere. sizeof's unit is "how many chars". For instance there was a cray machine that could only access 64bit words. sizeof(char) is still 1, with 64bit chars.
> zero to address zero. It is not using a NULL macro or other predefined symbol.
NULL is defined as literal 0.