Eric Blake wrote:
My prior patch forced an autogen.sh run, and I was surprised that the suggested './autogen.sh' lost the fact that I had previously used './autogen.sh -C' for speed.
* autogen.sh: Use config.status, if present and there were no arguments.
Thanks. This looks fine, too. I confirmed that it works as advertised, and am about to push this and the preceding 1/2. A small word of warning to our readers: For those new to configure's -C (--cache) option, be aware that its use comes with a responsibility (or price). You have to be careful to remove the cache periodically, in case something about your system or the configure-time tests makes it so a cached result is invalid. If you forget, and reuse an invalid cache, you can easily end up with subtle and hard-to-diagnose bugs.
I noticed this on the previous patch, because I blindly followed make's instructions to rerun ./autogen.sh, only to later realize that I just nuked my nice ./configure --enable-compiler-warnings=error settings.
Hmm, as long as make is smart enough to warn, and now that running ./autogen.sh with no arguments is reliable at maintaining an existing setup, I could even submit a followup patch to have make blindly run ./autogen.sh instead of dying with the error that the user has to run it. Any interest in such a followup?
I have a slight preference for automating it. The current failure+instructions do serve to tell the user that something unusual (and time-consuming) is about to happen, but it's easy to print a warning to that effect while automating the job.