On Tue, Jan 12, 2021 at 06:35:50PM -0800, Linus Torvalds wrote: > On Tue, Jan 12, 2021 at 6:14 PM Linus Torvalds > <torva...@linux-foundation.org> wrote: > > > > Ack. I'll assume I get this the usual ways from the arm64 tree.. > > Oh.. Actually, while you can use my ack if you decide to go this way, > I do wonder if it might not be better to introduce a notion of an > error at Kconfig time, and then we could make this whole GCC_VERSION > check be something that gets covered much earlier - when configuring > the kernel, rather than randomly (ok, very early) when building it. > > We already have the CONFIG_GCC_VERSION config variable, after all. > > And Kconfig already has an error functionality, which it uses for > things like compilers not found etc. > > So something like > > $(error-if,CC_IS_GCC && GCC_VERSION < 90100,"Gcc version too old") > > in the arm64 Kconfig file should do it.
$(error-if) seems to expect a y/n as a condition. We do have $(failure) and $(success) but they translate a (shell) command's return code to y/n. Even with something like: config GCC_IS_OLD def_bool CC_IS_GCC && GCC_VERSION < ... I can't get $(error-if,GCC_IS_OLD) to expand the config value, no matter what other. GCC_VERSION is also a config option in your example. I'll queue Will's patch in the meantime. -- Catalin