Assimp linking error - c++

Question

I just downloaded assimp 3.0 library and build the required make files with cmake, then compiled and build the library itself the process was successfull (with little modification to StepFile.h),
my assimp header folder is located in:
/usr/local/include
and my libassimp.a is located in:
/usr/local/lib
however when i specify library and header files in my command line project and try to test my project i get the following error:
Undefined symbols for architecture x86_64:
"Assimp::Importer::Importer()", referenced from:
_main in main.o
"Assimp::Importer::~Importer()", referenced from:
_main in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
and when i add -lassimp to Other Linker Flags i get the following errors:
Undefined symbols for architecture x86_64:
"_crc32", referenced from:
_unzReadCurrentFile in libassimp.a(unzip.c.o)
"_get_crc_table", referenced from:
_unzOpenCurrentFile3 in libassimp.a(unzip.c.o)
"_inflate", referenced from:
Assimp::XGLImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(XGLLoader.cpp.o)
Assimp::BlenderImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(BlenderLoader.cpp.o)
Assimp::XFileParser::XFileParser(std::__1::vector<char, std::__1::allocator<char> > const&) in libassimp.a(XFileParser.cpp.o)
_unzReadCurrentFile in libassimp.a(unzip.c.o)
"_inflateEnd", referenced from:
Assimp::XGLImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(XGLLoader.cpp.o)
Assimp::BlenderImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(BlenderLoader.cpp.o)
Assimp::XFileParser::XFileParser(std::__1::vector<char, std::__1::allocator<char> > const&) in libassimp.a(XFileParser.cpp.o)
_unzCloseCurrentFile in libassimp.a(unzip.c.o)
"_inflateInit2_", referenced from:
Assimp::XGLImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(XGLLoader.cpp.o)
Assimp::BlenderImporter::InternReadFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, aiScene*, Assimp::IOSystem*) in libassimp.a(BlenderLoader.cpp.o)
Assimp::XFileParser::XFileParser(std::__1::vector<char, std::__1::allocator<char> > const&) in libassimp.a(XFileParser.cpp.o)
_unzOpenCurrentFile3 in libassimp.a(unzip.c.o)
"_inflateReset", referenced from:
Assimp::XFileParser::XFileParser(std::__1::vector<char, std::__1::allocator<char> > const&) in libassimp.a(XFileParser.cpp.o)
"_inflateSetDictionary", referenced from:
Assimp::XFileParser::XFileParser(std::__1::vector<char, std::__1::allocator<char> > const&) in libassimp.a(XFileParser.cpp.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

I had the same issue recently. The actual solution for me was to ensure that the project where I was using the compiled libassimp.a also linked to libz.dylib rather than turn assimp into a .dylib.

Answer 2

i rebuild assimp so that the makefile yields three library files namely libassimp.3.0.255.dylib libassimp.3.dylib libassimp.dylib, i included them in my project and it worked.