Lessons learned from source upgrade from FreeBSD i386 9.2 Stable to FreeBSD i386 10.0 Release.

Lessons learned from source upgrade from FreeBSD i386 9.2 Stable to FreeBSD i386 
10.0 Release.

A)
Clang is needed to compile FreeBSD 10 due to use of the updated libstdc++ in world.
My workaround was to upgrade FreeBSD 9.2 to Clang 3.3 in the base system
and remove GCC 4.2.1 from base 9.2.
This was accomplished by using /etc/src.conf flags
WITH_CLANG=yes
WITH_LIBCPLUSPLUS=yes
WITH_CLANG_EXTRAS=yes
WITH_CLANG_IS_CC=yes
WITHOUT_GCC=yes
and recompiling world and FreeBSD as per
http://www.freebsd.org/doc/handbook/makeworld.html

B)
FreeBSD 10's change to pkg(8) (a.k.a. PKGNG) affects the portupgrade tools as 
well as the package tools.
Even if you are not using packages,
before upgrading to FreeBSD 10 install pkg(8) as described in:
http://www5.us.freebsd.org/doc/handbook/pkgng-intro.html
and be sure to run pkg2ng.

C)
FreeBSD 10 moves converters/libiconv into the base system, which directly or 
indirectly affects many ports.
This migration has largely been taken care of for the official packages,
however, if you are rebuilding from the ports tree
"pkg_delete libiconv" must be run,
or converters/libiconv must be deinstalled,
before your post OS recompile of all your ports.

Most of the iconv hardcodes have been addressed in the ports tree, but this is 
still being worked on.


I have suggested that this information be noted in the FreeBSD 10 release notes.