ports include /etc/src.conf? i.e. graphics/libfpx

Setting only base system source compiler optins in /etc/src.conf, for
instance

#
CXXFLAGS+=              -stdlib=libc++
CXXFLAGS+=              -std=c++11


which do NOT appear in /etc/make.conf, make building port
grahpics/libfpx complaining about unrecognized compiler options.

As far a sI know, /etc/src.conf is ONLY for building the source tree of
the operating system and make.conf is supposed to contain all stuff
necessary for compiling both world and ports, but /etc/src.conf is world
only.

Am I wrong?

Oliver

===>   libfpx-1.3.1.1 depends on file: /usr/local/sbin/pkg - found
===>  Extracting for libfpx-1.3.1.1
=> SHA256 Checksum OK for libfpx-1.3.1-1.tar.xz.
===>  Patching for libfpx-1.3.1.1
===>  Applying FreeBSD patches for libfpx-1.3.1.1
/usr/bin/sed -i '' -e '/^#include "fpxlib-config.h"/d'
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/basics/filename.cpp
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/oless/h/owchar.h
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/ole/gen_guid.cpp
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/fpxlib.h
===>  Configuring for libfpx-1.3.1.1
===>   FreeBSD 10 autotools fix applied to
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/configure
===>   FreeBSD 10 autotools fix applied to
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/aclocal.m4
===>   FreeBSD 10 autotools fix applied to
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/m4/libtool.m4
===>  Building for libfpx-1.3.1.1
Warning: Object directory not changed from original
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1
g++  -O2 -pipe -march=native -DHAVE_WCHAR_H -DHAVE_DLFCN_H
-DHAVE_SYS_TIME_H -DHAVE_SYS_PARAM_H -DHAVE_SYS_MOUNT_H -O3 -pipe
-march=native -fstack-protector -Werror -Wall -Wno-format-y2k -W
-Wno-unused-parameter -Wpointer-arith -Wno-uninitialized -fno-rtti
-fno-exceptions -fno-strict-aliasing -DHAVE_WCHAR_H -DHAVE_DLFCN_H
-DHAVE_SYS_TIME_H -DHAVE_SYS_PARAM_H -DHAVE_SYS_MOUNT_H
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/oless/h
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/jpeg
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/ole
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/basics
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/ri_image
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/oless
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/fpx
-I/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/. -I/usr/local/include
-D_UNIX -stdlib=libc++ -std=c++11 -c
/usr/ports/graphics/libfpx/work/libfpx-1.3.1-1/basics/geometry.cpp -o
geometry.o
cc1plus: error: unrecognized command line option "-stdlib=libc++"
cc1plus: error: unrecognized command line option "-std=c++11"
*** [geometry.o] Error code 1

Stop in /usr/ports/graphics/libfpx/work/libfpx-1.3.1-1.
*** [do-build] Error code 1

Stop in /usr/ports/graphics/libfpx.