gcc-4.8.4_3

[john drake via freebsd-questions]

Am running FreeBSD 10.2 and installed gcc-4.8.4_3

After installation received the following message from bcc:
for linking use -Wl,
-rparh=/usr/local/lib/gcc48

For ports leveraging USE_GCC,
USES=compiler, or
USES=fortran,
this happens transparently.

(1). What does this mean, and how do I make it happen transparently? How do I actually implement the USE approach?
(2). Can I make this transparent by altering the path command by adding /usr/local/lib/gcc48?
(3) Please supply me with answers to both approaches and their relative advantages/disadvantages?
(4). Also, supply me with the best approach.

Sent from my iPhone

[Shane Ambler]

Post by john drake via freebsd-questions
Am running FreeBSD 10.2 and installed gcc-4.8.4_3
for linking use -Wl,
-rparh=/usr/local/lib/gcc48
For ports leveraging USE_GCC,
USES=compiler, or
USES=fortran,
this happens transparently.

Firstly this only applies to using the FreeBSD ports system. For a
project that you manually compile within your home folder this will not
help.

See the porters handbook for help creating a port -
https://www.freebsd.org/doc/en/books/porters-handbook/

Post by john drake via freebsd-questions
(1). What does this mean, and how do I make it happen transparently?
How do I actually implement the USE approach?

In a port's Makefile you can add USE_GCC=4.8+ and the port will be built
using gcc v4.8 or higher. The ports infrastructure adds the relevant
settings to environment variables for this to work.

See /usr/ports/Mk/bsd.gcc.mk

There is also USE=compiler:ARGS for a more flexible approach. This
allows a port to specify it needs a compiler that supports C++11 and a
version of gcc or clang that supports c++11 will be chosen.

See /usr/ports/Mk/Uses/compiler

To work, both of these options rely on the projects build system
respecting environment variables such as CC CXX CFLAGS CXXFLAGS...
patches sometimes need to be applied otherwise.

USE=fortran is similar but only applies to using gcc or ifort as the
compiler when the project uses fortran.

Post by john drake via freebsd-questions
(2). Can I make this transparent by altering the path command by
adding /usr/local/lib/gcc48?

In most cases, adding one of the above options to a port's Makefile is
all that is needed.

Post by john drake via freebsd-questions
(3) Please supply me with answers to both approaches and their
relative advantages/disadvantages?

USE_GCC - specifies that only gcc can be used on this project.

USE=compiler - is more flexible as gcc or clang may be used as long as
it supports the features you need for the project.

The USE=compiler also allows a user to set FAVORITE_COMPILER in their
make.conf to influence the compiler chosen.

Post by john drake via freebsd-questions
(4). Also, supply me with the best approach.

That's a matter of opinion with some dependency on the way the project
is compiled. I would say USE=compiler is a better option but some
projects will only compile with gcc so need to have USE_GCC