"DSO missing from command line" while cross compiling mosquitto example

Question

I am trying to cross-compile the mosquitto example program. At first I compiled the mosquitto example on Host PC, it worked well. The makefile is as following:

CFLAGS=-Wall -ggdb -I../../lib -I../../lib/cpp
LDFLAGS=-L../../lib ../../lib/cpp/libmosquittopp.so.1 ../../lib/libmosquitto.so.1

.PHONY: all clean

all : mqtt_temperature_conversion

mqtt_temperature_conversion : main.o temperature_conversion.o
    ${CXX} $^ -o $@ ${LDFLAGS}

main.o : main.cpp
    ${CXX} -c $^ -o $@ ${CFLAGS}

temperature_conversion.o : temperature_conversion.cpp
    ${CXX} -c $^ -o $@ ${CFLAGS}

clean : 
    -rm -f *.o mqtt_temperature_conversion

Then I add the following lines to cross compile this program:

CXX=arm-unknown-linux-gnueabi-gcc
AR=arm-unknown-linux-gnueabi-ar
AS=arm-unknown-linux-gnueabi-as
LD=arm-unknown-linux-gnueabi-ld
RANLIB=arm-unknown-linux-gnueabi-ranlib

Then it gives a error message:

/home/Tools/tool_chain/bin/../lib/gcc/arm-unknown-linux-
gnueabi/5.4.0/../../../../arm-unknown-linux-gnueabi/bin/ld: main.o: 
undefined reference to symbol '_ZdlPv@@GLIBCXX_3.4'


/home/Tools/tool_chain/bin/../sysroot/usr/lib/libstdc++.so.6: 
error adding symbols: DSO missing from command line

I am very confused. I googled for this error, but none of them seems to be relevant. Cause when I compiled with the host PC compiler, everything works. So it should not be a lib problem.

update: So I could not figure out what happened, then I made a test project myself. The Makefile is as follows:(I ignored the cross tool chain variabl parts to save some place)

CFLAGS=-Wall -ggdb -I../../lib -I../../lib/cpp
LDFLAGS=-L../../lib ../../lib/cpp/libmosquittopp.so.1 ../../lib/libmosquitto.so.1


mqtt: main.o
    ${CXX} $^ -o $@ ${LDFLAGS}

main.o: main.cpp
    ${CXX} -c $^ -o $@ ${CFLAGS}

And it worked?! I flashed it to the board the executable seems to be correct.

Now I am more confused

Answer 1

LD=arm-unknown-linux-gnueabi-ld

Don't use ld directly, ever. You want to use g++ as the driver that calls your linker, otherwise you will have linker problems.

LD=$(CXX)