Compilation error: Undefined symbols for architecture x86_64 - compilation

Question

I am trying to use a fortran library to perform FFT called "2Decomp&FFT"(http://www.2decomp.org/download.html). This library has a in-built FFT engine and works fine with my code. In order to use FFTW3 engine with this library, instead of its in-built engine, the instructions say:
Edit 'src/Makefile.inc' file in 2DECOMP, change the FFT engine to 'FFT=fftw3'. You also need to set the FFTW_PATH variable in the same file to point to your FFTW installation. Then recompile everything.
I installed FFTW3.3 on my local Mac and followed the instructions and recompiled the library. However after that when I am trying to compile my code with the library, I am getting the following error while linking.
Undefined symbols for architecture x86_64:
"_dfftw_destroy_plan_", referenced from:
___decomp_2d_fft_MOD_decomp_2d_fft_finalize in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_execute_dft_", referenced from:
___decomp_2d_fft_MOD_c2c_1m_z in lib2decomp_fft.a(fft_fftw3.o)
___decomp_2d_fft_MOD_c2c_1m_x in lib2decomp_fft.a(fft_fftw3.o)
___decomp_2d_fft_MOD_c2c_1m_y in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_execute_dft_c2r_", referenced from:
___decomp_2d_fft_MOD_c2r_1m_x in lib2decomp_fft.a(fft_fftw3.o)
___decomp_2d_fft_MOD_fft_3d_c2r in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_execute_dft_r2c_", referenced from:
___decomp_2d_fft_MOD_fft_3d_r2c in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_plan_many_dft_", referenced from:
___decomp_2d_fft_MOD_c2c_1m_z_plan in lib2decomp_fft.a(fft_fftw3.o)
___decomp_2d_fft_MOD_c2c_1m_x_plan in lib2decomp_fft.a(fft_fftw3.o)
___decomp_2d_fft_MOD_c2c_1m_y_plan in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_plan_many_dft_c2r_", referenced from:
___decomp_2d_fft_MOD_init_fft_engine in lib2decomp_fft.a(fft_fftw3.o)
"_dfftw_plan_many_dft_r2c_", referenced from:
___decomp_2d_fft_MOD_init_fft_engine in lib2decomp_fft.a(fft_fftw3.o)
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status
make: *** [Sora_v71] Error 1
Here is a minimal code I have written which calls this library:
program test
use decomp_2d
use decomp_2d_fft
integer n, pr, pc
call decomp_2d_init(n,n,n,pr,pc)
call decomp_2d_fft_init
stop
end
Here is the Makefile I am using (DECOMP2D is the environment variable set to the folder containing the library) :
## ------------------------------------------------------------------------
# Lines included for using the 2decomp libraries
INC_2DECOMP = -I$(DECOMP2D)/include/
LIB_2DECOMP = -L$(DECOMP2D)/lib/ -l2decomp_fft
## ------------------------------------------------------------------------
RM = rm
SRCDIR = .
LIBDIR = .
BIN = a.out
OBJS = main.o
## ------------------------------------------------------------------------
# default command for compiler, linker
FC = mpif90
FFLAGS = $(F90FLAG) $(INC_2DECOMP)
LFLAGS = $(F90FLAG) $(LIB_2DECOMP) -L$(LIBDIR)
## ------------------------------------------------------------------------
# default action
all: $(BIN)
$(BIN): $(OBJS)
#echo Linking $(BIN) .....
$(FC) $(OBJS) $(LFLAGS) $(FFLAGS) -o $#
.f.o:
#echo Compiling $*.f
$(FC) $(LFLAGS) $(FFLAGS) -c $(SRCDIR)/$*.f
clean:
#echo 'Cleaning .....'
$(RM) -f core *.o *~ *.L *.O $(BIN) $(SIZE_FILE)