root5: configure: c++11 mode is requested but the current compiler does not support it.

[ryandesign (Ryan Carsten Schmidt)]

​root5 fails to build on Mojave. The error message says:

configure: c++11 mode is requested but the current compiler does not support it.

This is clearly incorrect; the MacPorts clang++ 5.0 compiler being used does of course support C++11.

It's unclear why the port is forcing the use of MacPorts clang++ 5.0, rather than the more recent version of clang provided by Xcode.

[cjones051073 (Chris Jones)]

This is expected. root5 does not support the missing '/usr/include' directory on macOS10.14. You need to install the extra SDK header package from Xcode. e.g.

​https://apple.stackexchange.com/questions/337940/why-is-usr-include-missing-i-have-xcode-and-command-line-tools-installed-moja

It is also intentional that it does not use the system compiler, as it does not work with that. I forget exactly why...

root5 is obsolete. I thought about just not allowing it on 10.14+, but as it works with the above optional package installed I decided to keep it for now. I most likely will do this for 10.15+

[ryandesign (Ryan Carsten Schmidt)]

Could the port detect this situation and provide the user with a better error message explaining what to do? Currently, it just looks like a build failure, and if the user inspects the log, they will get an inaccurate error message that doesn't tell them how to solve the problem.

[cjones051073 (Chris Jones)]

yes, I guess that could(should) be done...

[Chris Jones <jonesc@…>]

In 1c16b9c5f8ef8c532784cc2ac617e70f21426e4d/macports-ports (master):

root5: obsolete on Darwin19+ and add check for /usr/include on Darwin18
Closes:#58618