Ch18 - Arbitrary Precision: strict code

[ylme]

https://github.com/drh/cii/blob/master/src/ap.c#L361

Before AP_new(0) , call AP_free(&z) making code stricting, Does it ?

if (endp == p) { endp = (char *)str; z = AP_new(0); }

[juniskane]

I don't know what you mean by "strict code" or "stricting", but this looks like a memory leak of old value of 'z', that was allocated by mk() earlier. It is not in book's errata.

But I don't think the branch if (endp == p) here is ever taken. This is because called XP_fromstr() can return with that condition only if passed string contains zero valid digits in base. But AP_fromstr() validates the digits before calling XP_fromstr() and before z = mk(((k*n + 7)&~7)/8) call. However if this validation fails with first digit (the endp == p case), then n is 0 which makes entire expression 0 and mk() asserts on assert(size > 0) line:

Uncaught exception Assertion failed raised at src/ap.c:26
aborting...

This exception makes the error handling block dead code, and is bug in itself. Call char *end; AP_fromstr("A", 10, &end); to easily reproduce.