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0 pointsaltfredd7y ago0 comments

"Configure often detects features by compiling a binary and executing it" — I am not sure, where this impression comes from. Autotools as whole have excellent cross-compilation support. Autoconf has feature-detection routines, checking for presence of headers, exported symbols and pkg-config files. None of those trigger "execute the binary" part when cross-compiling. In addition, custom-written host-side checks can easily be skipped when cross-compiling (either by code of check itself or by user via environent-variable overrides). Do you you know of any build system, that handles this better?

Cmake and several other buildsystems either don't support cross-compilation at all (because their primary audience is Windows) or use pkg-config only. Few others are nightmarish parody of autotools with much worse support. Most don't have ounce of autotools features.

I know many projects, that offer horrible autotools "support": for example, glib2 autotools scripts can't be cross-compiled to Android without ample application of hacks. But those issues are caused by incompetence and lack of testing, not some innate fault of Autotools. When such projects migrate to something else, their cross-compilation process becomes WORSE.

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tbirdz7y ago

The impression comes from having to deal with multiple configure sciripts that do that very thing.

The capabilities may be there, but in my experience many if not most projects do not use those capabilities. Most autotools based projects I've had to cross build are made by people without a great understanding of autotools internals and capabilities, so they often end up copy pasting things blindly from other projects until they get their native build working. Advanced build system stuff like cross building is not even considered.

These builds end up trying to execute a binary to do feature tests, or compile a program and use that to generate code, or do any number of things that break when cross building.

Would things be worse without autotools? Maybe so. In my personal experience projects using a simple Makefile were much easier to cross build and package than ones using autotools, but that's probably confounded by projects using a Makefile being simpler overall.