undefined symbol using pybind11 cmd

Question

i want to use pybind11 to create .so , my code contains this header

`#include <pybind11/pybind11.h>
#include <gst/gst.h>
#include <glib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <sys/time.h>
#include "nvbufsurface.h"`

when i use :

c++ -O3 -Wall -shared -std=c++11 -fPIC python3-config --cflags --ldflags -I/usr/local/lib/python3.6/dist-packages/pybind11/include -I/home/xxx/deepstream_sdk_v4.0.2_x86_64/sources/includes pkg-config --cflags gstreamer-1.0,opencv -L/home/xxx/deepstream/deepstream-4.0/lib/ -lnvbufsurface -lcudart -lnvdsgst_meta -lnvds_meta -lnvdsgst_helper pkg-config --libs gstreamer-1.0,opencv example.cpp -o example.so

or i use:

c++ -O3 -Wall -shared -std=c++11 -fPIC pkg-config --cflags gstreamer-1.0 -L/home/xxx/deepstream/deepstream-4.0/lib -lnvbufsurface -lnvdsgst_meta -lnvds_meta -lnvdsgst_helper -lm -I/home/xxx/deepstream_sdk_v4.0.2_x86_64/sources/includes pkg-config --libs gstreamer-1.0 python3 -m pybind11 --includes example.cpp -o examplepython3-config --extension-suffix

and i import example in python3 i get undefined symbol: NvBufSurfaceSyncForDevice Please help me

Answer 1

All those linker flags should come after the cpp that needs them. I separated your code into different lines for readability.

c++ -O3 -Wall -shared -std=c++11 -fPIC  \
`pkg-config --cflags gstreamer-1.0` \
-I/home/xxx/deepstream_sdk_v4.0.2_x86_64/sources/includes \
`python3 -m pybind11 --includes` \
example.cpp -o example`python3-config --extension-suffix` \
`pkg-config --libs gstreamer-1.0` \
-L/home/xxx/deepstream/deepstream-4.0/lib -lnvbufsurface -lnvdsgst_meta \
-lnvds_meta -lnvdsgst_helper \
-lm