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A Q&A + blog post on NASM label delta arithmetic (Announce)

posted by ecm  , Düsseldorf, Germany, 28.03.2026, 13:47

I finished a pair of pages that I'd been preparing for a while. The first page is a question and answer on stackoverflow.com, asking how to do arbitrary calculations on NASM assembly language labels: https://stackoverflow.com/questions/79916187/how-c...itrary-calculations-on-assembly-language-labels

The answer lists four different approaches, but the point of this Q&A was to introduce a canonical explanation of label delta arithmetic. A label delta is the delta (difference) between two labels that live in the same section of an assembly language source text. Label delta arithmetic then is to do calculations involving one or more label deltas.

The second page I wrote is an article in my blog, quoting many instances in which I or a few others have referred to label delta arithmetic: https://pushbx.org/ecm/dokuwiki/blog/pushbx/2026/0328_comments_on_label_delta_arithmetic

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• A Q&A + blog post on NASM label delta arithmetic - ecm, 28.03.2026, 13:47 (Announce)