Update math macros to avoid computing callable arguments more than once #391
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Currently, if you pass an a callable argument to (e.g.) the
max
macro, the argument will be computed more than once.max(expensive_function(a), expensive_function(b))
will expand to:The compiler can't always optimize these calls away, as seen in the Godbolt disassembly here. This PR uses the GCC
typeof
extension to avoid these unnecessary calls where possible, falling back to the existing macros should that feature be unavailable. (Testing for it with the latest Arduino SDK shows that the extension is available.)