makefile: how to perform “ranlib” operation correctly - c++

Question

I downloaded a third party lib( Library link) which installs and compiles properly. It creates multiple object file (*.o), rather than creating executable, it's using gnu libtool to do some scripting. I plan to make some changes in some function; however, given I am new to linux, I thought to avoid libtool and just create executable.
I wrote a small makefile to link multiple object files and libraries and create an executable. All object files already exists. One library is as archive file (libtaucs.a). Based on online resouce, I came to know that I have to perform "ranlib" utlity as suggested here link. However, I get the following error:
$ make
make: *** No rule to make target `ranlib', needed by `test_me_DKU'. Stop.
Here is my makefile which I am using to link already existing object file (disclaimer: I barely understand makefile;so, you may find lots of error)
# Here is a simple Make Macro.
LINK_TARGET = test_me_DKU
# Here is a Make Macro that uses the backslash to extend to multiple lines.
##OBJS = tsnnls_test.o
OBJS = libtsnnls_la-taucs_malloc.o libtsnnls_la-taucs_ccs_order.o \
libtsnnls_la-taucs_ccs_ops.o libtsnnls_la-taucs_vec_base.o \
libtsnnls_la-taucs_complex.o libtsnnls_la-colamd.o \
libtsnnls_la-amdbar.o libtsnnls_la-amdexa.o \
libtsnnls_la-amdtru.o libtsnnls_la-genmmd.o \
libtsnnls_la-taucs_timer.o libtsnnls_la-taucs_sn_llt.o \
libtsnnls_la-taucs_ccs_base.o libtsnnls_la-tlsqr.o \
libtsnnls_la-tsnnls.o libtsnnls_la-lsqr.o \
tsnnls_test.o
# Here is a Make Macro defined by two Macro Expansions.
# A Macro Expansion may be treated as a textual replacement of the Make Macro.
# Macro Expansions are introduced with $ and enclosed in (parentheses).
REBUILDABLES = $(OBJS) $(LINK_TARGET)
clean :
rm -f $(REBUILDABLES)
echo Clean done
all : $(LINK_TARGET)
echo All done
RANLIB = ranlib
LIBTARGET= /usr/local/lib/taucs_full/lib/linux/libtaucs.a
tsnnls_test_LDADD = $(LDADD)
LIBS = -largtable2 -llapack -lblas -lquadmath $? $(RANLIB) $(LIBTARGET) -lm
# Here is a Rule that uses some built-in Make Macros in its command:
# $# expands to the rule's target, in this case "test_me.exe".
# $^ expands to the rule's dependencies, in this case the multiple files
# defined in OBJS (*.o)
$(LINK_TARGET) : $(OBJS) $(tsnnls_test_LDADD) $(LIBS)
g++ -g -o $# $^
Also, can someone please also explain this command ?
g++ -g -o $# $^

Answer 1

Your error is that you put $(tsnnls_test_LDADD) and $(LIBS) in the prerequisites line. That isn't correct. You want those on the linking line. They are flags to the linker.
You also don't want ranlib in LIBS because it is a command that needs to be run and not a flag to the linker.
That all being said you don't appear to be creating a static library (.a file) so you shouldn't need ranlib at all. Alternatively, since you probably do want to be making a library and not an executable (binary). You need to run ranlib on the .a file as indicated in the question/answer you linked.