mpusz/mp-units

📝 What Add two entries to docs/getting_started/faq.md, each built from an answer that already exists in GitHub Discussions but is findable only by someone who knows to search there: #712 - why you never instantiate derived_unit (or any other derived_XXX type) yourself, and what to write instead. #699 - why QuantityOf and QuantityPointOf do not take a Reference, and how to check for a specific unit when you genuinely need to. Note that the two concepts differ: QuantityOf constrains against a quantity specification, while QuantityPointOf accepts either a quantity specification or an absolute point origin. Read the concept definitions rather than trusting this summary. Both discussions have an accepted answer, so the content exists. The work is editorial: turn an answer written to one person into an entry that reads for everyone. 💡 Why The FAQ is where a reader looks before filing anything, and #712 arrived from someone who followed the documentation and hit a compilation error, w

📝 What Add a small CI check that verifies mp-units compiles to the same machine code as hand-written equivalents, on one reference configuration. Concretely: Create a dedicated translation unit with a few abstraction/baseline pairs: an mp-units function and the equivalent raw function (for example, speed from distance and time). Emit assembly with -S at the release optimization level. Extract each function's assembly, strip incidental tokens (labels, comments, directives, alignment padding), and assert each pair is equivalent. Byte-identical after normalization is the target for a truly zero-overhead operation. Wire it as a CTest test on a single reference configuration (for example, the latest Clang, Release, x86-64) so it gates pull requests. Keep the first version deliberately minimal: a handful of operations, one configuration, byte-identical comparison. The set can grow later. 💡 Why mp-units promises zero runtime overhead, but today that promise is only checked manually on