verbose builds

[Ryan Schmidt]

On Jul 25, 2018, at 05:32, Rainer Müller wrote:

>> Would it be useful if port(1) had --disable-silent-rules
>> among configure.args by default? Or at least with port -vs?
>> Not having the actual commands renders the main.log a bit useless.
> 
> Yes, --disable-silent-rules should be used whenever possible. However,
> only configure scripts using automake will provide that option. Other
> configure scripts might also fail when unknown options are passed on the
> command line. Therefore I do not think it is not possible to make it a
> default.

I agree with Rainer that adding it to the default configure args now could break a lot of ports. If we had had it there from the beginning, ports that aren't compatible with it would already be removing it, but we didn't, and I don't want to break those ports now and spend the next few years finding and fixing them. If ports were already indicating via some variable that they use automake, we could add the flag only for those ports, but no such indication exists. So I think each port has to be responsible for ensuring a verbose build occurs, by whatever means is appropriate for that port. For automake ports, we usually add --disable-silent-rules to configure.args but one could add V=1 to build.args instead; other build systems may honor one or both of those methods too, or they may have other ways of achieving it (the cmake portgroup takes care of cmake's unique way of doing it, for example), or it may requires patches to the build system.

The reason why we didn't have that flag in the default configure args from the beginning is that the flag didn't used to exist; automake used to always use verbose rules. Then later (in automake 1.11), the option to use silent rules was introduced.

https://autotools.io/automake/silent.html

Then later, silent rules were made the default. We still want them disabled for MacPorts though, so that main.log files that users attach to bug reports contain useful information, so as projects' build systems are rebuilt with newer versions of autotools, a flag to disable the silent rules has to be added to those ports.

If we did want to add the flag by default, we would not want to put it in configure.args, because the purpose of configure.args is to be set by portfiles, and tons of them do; if we provided a default value for it in base, most ports would override it. We could put it in configure.pre_args instead, along with --prefix=${prefix}. Those ports that override configure.pre_args because they don't support --prefix=${prefix} probably don't support --disable-silent-rules either.

After writing the above, it occurs to me that adding V=1 to build.pre_args or build.post_args by default might be a solution. Unlike configure scripts, some of which complain about unknown flags being used, make isn't going to complain about unknown variables being set. There is of course still a possibility that some Makefiles may use a variable called V for some other purpose and that by overriding it to be 1 we might break those Makefiles. But my guess is that setting V=1 by default would break far fewer ports than using --disable-silent-rules by default. There are already 73 portfiles that set V=1 manually, though there are a couple that set it to different values: cmus sets V=2, and lua51 sets V to a version number. And of course we have no idea how many ports' Makefiles internally use a variable called V that the Portfiles aren't currently setting.