Avoid nullptr subtraction when flushing scalars at EOF #43

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weaselbot wants to merge 2 commits from weaselbot/weaseljson:weaselbot/issue-40 into main

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2 Commits

Author	SHA1	Message	Date
weaselbot	bf3f2fe810	Avoid nullptr subtraction using intptr_t casts ... Andrew's review on the previous fix noted that the nullptr checks produced slightly worse codegen. Replace the pointer subtraction with intptr_t subtraction, which avoids the undefined behaviour of subtracting two null pointers without introducing extra branches.	2026-06-29 15:14:36 -04:00
weaselbot	bd53e57b8e	Avoid nullptr subtraction when flushing scalars at EOF ... When a scalar ends exactly at a chunk boundary, Parser3::parse resets dataBegin and writeBuf to the new buf at the start of every call. On the EOF call buf is null, so both pointers become null. The final flushNumber/flushString then computed len as buf - dataBegin, i.e. nullptr - nullptr, which is undefined behaviour in C++. Compute the flush length safely: if dataBegin is null (or, for raw mode, buf is null), treat the length as zero. Use an empty string literal as a non-null data pointer for the zero-length, done=true callback so callers still receive the completion signal. Add a regression test covering a number that fills its chunk exactly and is finalized by an EOF call. Fixes #40	2026-06-29 13:57:58 -04:00