> - Width of an int If your software depends on this, you're doing it wrong. As you said, depending on the existence of <stdint.h> is just fine, and you can t

> - Width of an int If your software depends on this, you're doing it wrong. As you said, depending on the existence of <stdint.h> is just fine, and you can then specify what you need. Even in the incredibly rare case of needing the width of int (serializing inputs and outputs of existing libraries interoperably on multiple machine ABIs) <limits.h> has you covered, albeit in an awkward way, unless you can assume POSIX and thus have WORD_BIT. > - Endianness If your software depends on this, you're doing it wrong. If the wire/file format is little endian, input[0] | input[1] << 8, if stupid-endian, input[0] << 8 | input[1]. > - Search through a list of libraries until one is found that provides a requested function, then add that library to LDFLAGS This is the exact opposite of what I want! If I'm depending on other libraries, I want that dependency explicitly listed and settable, not automagically found. > - Does the C compiler work? How is this reasonable to test? If it doesn't work, it can't actually do anything about it. > - Do compiled binaries run on the build machine? Totally ignores cross compilation, or deploys to other places -- e.g. containers. > And it gives you control over things like: These are generally useful, but the complexity required for autoconf is a huge cost to pay. > Automake gives you: All useful, yes. But these have never seemed to be particularly hard to do manually.