compiler.whitelist and compiler installation side-effects

[René J.V. Bertin]

On Sunday September 20 2015 12:35:03 Ryan Schmidt wrote:

>Range filtering is already included in the compiler_blacklist_versions portgroup. An example is given in the portgroup:

Yes,

># compiler.blacklist-append {clang >= 421.11.66 < 444}

That only applies to the Xcode clang versions, as far as I can tell.
>
>Trying to use "macports-clang" as the compiler name is not supported because that relies on the user having selected a version of MacPorts clang using "port select"

Why? Why would it not be possible to check if macports-clang (or clang-mp) newer or older than some version is installed, or why would it depend on having used port select? 
Extending range selection to MacPort's clang versions only means that it becomes possible to use a short-hand notation for something that would otherwise require listing each versions concerned explicitly. It's not like it introduces a forbidden feature ...

>Looks like 3.5 and later require libc++ to exist; it doesn't exist on 10.6 unless the user puts it there per the instructions in the LibcxxOnOlderSystems wiki page.

3.7 also fails to build on a system that does have libc++, or so at least I have been told. I've never bothered to install clang > 3.4 on my 10.6 system; gcc-mp-4.8+ worked just fine for me and was a lot faster than even clang 3.4 .

R.