I think build systems shouldn't have variables that affect flags

Having cmake, meson etc parse your flags and options is more cumbersome than it worth, and is usually a source of bugs.

I think the correct approach for any new toolchain should be to have a separate toolchain file for everything you want to do. A toockhain file should only define binaries and flags.

want to have lto? use the toolchain with -flto

want to have PIC? use the toolchain that has -fPIC

Having cmake take a variable like -DINTERPROCEDURAL_OPTIMIZATION to have a lot build with the same toolchain just leads to bugs. Often some projects simply ignore your flags anyway

Also, flags change as compiler version changes. So you have to constantly maintain the build system.

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I'm honestly tired of projects ignoring my flags, for example llvm compiler RT ignoring add_linkoptions, or cmke ignoring add_compile_options for building std module. I had to use old cxx init variables.

I think this was a bad idea from the beginning, A modern build system should just have a nice DSL, and take flags and executables and that's it. It shouldn't deal with other build systems, it shouldn't act as a package manager.

It should be a binary, not a python package so the scripting should be built in.

Anyway, this was my rant/discussion or whatever.

https://redd.it/1qz55an
@r_cpp