aws-sdk-cpp: unresolved symbols - c++

Question

I am trying to build a simple example using aws sdk cpp. But I am stumbled on a building step. I am linking libaws-cpp-sdk-s3.so library, which is supposed to have all symbols from the source file. But the linker cannot even find a couple of them. The source file is:
#include <aws/core/Aws.h>
int main( int argc, char ** argv)
{
Aws::SDKOptions options;
Aws::InitAPI(options);
{
// make your SDK calls here.
}
Aws::ShutdownAPI(options);
return 0;
}
by using this Makefile:
CC = g++
CFLAGS = -g -c -Wall -std=c++11
LDFLAGS = -g
EXECUTABLE = ex1
RM = rm -f
SOURCES = main.cpp
OBJS = $(SOURCES:.cpp=.o)
all: $(EXECUTABLE)
$(EXECUTABLE): main.o -laws-cpp-sdk-s3
$(CC) $(LDFLAGS) main.o -o $#
main.o: main.cpp
$(CC) $(CFLAGS) $^ -o $#
.PHONY: clean
clean:
$(RM) $(EXECUTABLE) $(OBJS) $(SOURCES:.cpp=.d)
When I run make, I got this error. But why? I built
g++ -g main.o -o ex1
main.o: In function main':
/home/username/workspace/ex1/src/main.cpp:6: undefined reference toAws::InitAPI(Aws::SDKOptions const&)'
/home/username/workspace/ex1/src/main.cpp:12: undefined reference to `Aws::ShutdownAPI(Aws::SDKOptions const&)'
collect2: error: ld returned 1 exit status
Makefile:13: recipe for target 'ex1' failed
make: *** [ex1] Error 1

Answer 1

I don't see where you are linking libaws-cpp-sdk-core
You probably need:
$(EXECUTABLE): main.o -laws-cpp-sdk-s3 -laws-cpp-sdk-core
$(CC) $(LDFLAGS) main.o -o $#