Is it a discouraged behavior to limit port's target OS version?

[Ardie H. Hwang]

Hi all,
I need an advice or two regarding the problem I met.

I am preparing a submission of new port, which depends on <iconv.h>: `databases/mariadb-connector-c`.
Everything went okay, until Poudriere test in 9.3-RELEASE jail reported build failure. Apparently <iconv.h> has been added to base system since 10.0-RELEASE.

The question is: this limiting OS version for this port, is this a discouraged idea? The method I am thinking is to display error if OS version is less than 10.x, upon checking OSVERSION makevar in Makefile. But this will discriminate against fellow 9.x users.
I have another solution of adding `converters/iconv` (libiconv.so) as this port's library dependency. However, I am worried that doing this might cause problem on 10.x versions.

Can someone tell me what to do regarding this <iconv.h> on 9.x?

-- 
Ardie H. Hwang
----------------
email: iam at ardiefox.me
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