make step gives error "g++: error: /:: No such file or directory"

[hmqq]

i'm trying to install dlplugin. there is no problem on ./configuration step but when i use "make" it gives me following error.

make output:
Making all in examples
make[1]: Entering directory '/home/haya/Documents/dlplugin/examples'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/haya/Documents/dlplugin/examples'
Making all in include
make[1]: Entering directory '/home/haya/Documents/dlplugin/include'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/haya/Documents/dlplugin/include'
Making all in src
make[1]: Entering directory '/home/haya/Documents/dlplugin/src'
make all-am
make[2]: Entering directory '/home/haya/Documents/dlplugin/src'
/bin/bash ../libtool --tag=CXX --mode=compile g++ -DHAVE_CONFIG_H -I. -I../include -I../src /usr/local/include/raptor2: -pthread -I/usr/local/include -I/usr/local/include/dlvhex2/bm3.7.0/ -DPLUGIN_DIR='"/usr/local/lib/dlvhex2/plugins"' -W -Wall -g -O2 -MT Answer.lo -MD -MP -MF .deps/Answer.Tpo -c -o Answer.lo Answer.cpp
libtool: compile: g++ -DHAVE_CONFIG_H -I. -I../include -I../src /usr/local/include/raptor2: -pthread -I/usr/local/include -I/usr/local/include/dlvhex2/bm3.7.0/ -DPLUGIN_DIR="/usr/local/lib/dlvhex2/plugins" -W -Wall -g -O2 -MT Answer.lo -MD -MP -MF .deps/Answer.Tpo -c Answer.cpp -fPIC -DPIC -o .libs/Answer.o
g++: error: /usr/local/include/raptor2:: No such file or directory
Makefile:605: recipe for target 'Answer.lo' failed
make[2]: *** [Answer.lo] Error 1
make[2]: Leaving directory '/home/haya/Documents/dlplugin/src'
Makefile:455: recipe for target 'all' failed
make[1]: *** [all] Error 2
make[1]: Leaving directory '/home/haya/Documents/dlplugin/src'
Makefile:493: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1

/usr/local/include/raptor2 is the path that i used for Raptor environment variable
RAPTOR_CFLAGS="/usr/local/include/raptor2
RAPTOR_LIBS="/usr/local/lib/libraptor2.so

I don't know what and where i'm doing wrong. kindly guide me.
@peschue @alexleutgoeb @tonico