lang/gcc48 fails to build

[Rainer Hurling]

I am using lang/gcc48 for a long time now on FreeBSD 11.0-CURRENT. From 
time to time I have to rebuild the port. This is the first time, that I 
get the following error:


[..snip..]
gmake[4]: Verzeichnis „/usr/ports/lang/gcc48/work/build/gcc“ wird betreten
c++   -O2 -pipe -DLIBICONV_PLUG -fno-strict-aliasing  -DLIBICONV_PLUG 
-DIN_GCC   -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W 
-Wall -Wno-narrowing -Wwrite-strings -Wcast-qual 
-Wmissing-format-attribute -pedantic -Wno-long-long -Wno-variadic-macros 
-Wno-overlength-strings   -DHAVE_CONFIG_H -DGENERATOR_FILE  -o 
build/gengtype \
     build/gengtype.o build/errors.o build/gengtype-lex.o 
build/gengtype-parse.o build/gengtype-state.o build/version.o 
../build-x86_64-portbld-freebsd11.0/libiberty/libiberty.a
build/gengtype  \
                     -S .././../gcc-4.8.5/gcc -I gtyp-input.list -w 
tmp-gtype.state
/bin/sh .././../gcc-4.8.5/gcc/../move-if-change tmp-gtype.state gtype.state
build/gengtype  \
                     -r gtype.state
echo timestamp > s-gtype
c++ -c   -O2 -pipe -DLIBICONV_PLUG -fno-strict-aliasing  -DLIBICONV_PLUG 
-DIN_GCC   -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W 
-Wall -Wno-narrowing -Wwrite-strings -Wcast-qual 
-Wmissing-format-attribute -pedantic -Wno-long-long -Wno-variadic-macros 
-Wno-overlength-strings   -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -Ibuild 
-I.././../gcc-4.8.5/gcc -I.././../gcc-4.8.5/gcc/build 
-I.././../gcc-4.8.5/gcc/../include 
-I.././../gcc-4.8.5/gcc/../libcpp/include -DLIBICONV_PLUG \
	-o build/genflags.o .././../gcc-4.8.5/gcc/genflags.c
c++: warning: treating 'c' input as 'c++' when in C++ mode, this 
behavior is deprecated
In file included from .././../gcc-4.8.5/gcc/genflags.c:26:
In file included from ./tm.h:16:
./options.h:4293:3: error: redefinition of enumerator 'OPT_C'
   OPT_C = 129,                               /* -C */
   ^
./options.h:4290:3: note: previous definition is here
   OPT_C = 126,                               /* -C */
   ^
./options.h:4301:3: error: redefinition of enumerator 'OPT_d'
   OPT_d = 137,                               /* -d */
   ^
./options.h:4299:3: note: previous definition is here
   OPT_d = 135,                               /* -d */
   ^
[..snip..]
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
Makefile:3840: die Regel für Ziel „build/genflags.o“ scheiterte
gmake[4]: *** [build/genflags.o] Fehler 1
gmake[4]: Verzeichnis „/usr/ports/lang/gcc48/work/build/gcc“ wird verlassen
Makefile:3908: die Regel für Ziel „all-gcc“ scheiterte
gmake[3]: *** [all-gcc] Fehler 2


Is this a known error? It seems, there is something odd with C++ mode 
and C files?

This happens on a FreeBSD 11.0-CURRENT box with r290541 (bapt's 
locale/localedef updates of base from the weekend included).

Please tell me, if I should provide more information.

Thanks in advance,
Rainer Hurling