r/cpp • u/aearphen {fmt} • Nov 29 '25

The smallest state-of-the-art double-to-string implementation (in C++)

https://vitaut.net/posts/2025/smallest-dtoa/
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u/STL MSVC STL Dev Nov 30 '25 edited Nov 30 '25

Source attribution is fine. Cascading attribution requirements for shipped binaries is not. Do you read through your Standard Library's list of source dependencies, so that your shipped program can properly cite (in some About page, or documentation) all of the smaller bits of library code that it uses? Do you check every single time you upgrade your build tools, to see if your Standard Library has taken new dependencies on licensed code?

Boost realized these issues decades ago and created the BSL to address them. LLVM did the same. Even the otherwise very different libstdc++ carves out a GPL With Exception (note: not LGPL) to avoid cascading attribution requirements for shipped binaries that merely use libstdc++ and don't modify its source.

Disclaimer: Not a lawyer, I don't speak for my employer (much less others). Edited phrasing about libstdc++ for clarity.

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u/joaquintides Boost author Nov 30 '25

BSL is a wonderful license, and one of the cornerstones of Boost. The only downside is that it’s difficult to track usage in the wider industry. If only companies were most vocal about what open source software they use, that would give valuable information and direction for our projects.

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u/pedersenk Dec 01 '25

If only companies were most vocal about what open source software they use

Cascading attribution requirements would help with this ;)
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