c++ boost on mac compile error - c++

I've tried with/without -m64 option, it is not working. How should I fix this?
Undefined symbols for architecture x86_64:
"boost::system::system_category()", referenced from:
boost::asio::error::get_system_category() in main-6996c8.o
boost::system::error_code::error_code() in main-6996c8.o
___cxx_global_var_init.2 in main-6996c8.o
"boost::system::generic_category()", referenced from:
___cxx_global_var_init in main-6996c8.o
___cxx_global_var_init.1 in main-6996c8.o
ld: symbol(s) not found for architecture x86_64

First, are you using Xcode or using command line?
Second, the problem probably is that the include dir and lib dir are not set up correctly.
Third, you can go to /usr/local/include to check if you have boost headers and go to /usr/local/lib to check if you have boost libs.

Related

OpenCV4 on XCode — opencv2/core.hpp not found

so I've been trying to install OpenCV with C++ on my mac using this tutorial: https://medium.com/#jaskaranvirdi/setting-up-opencv-and-c-development-environment-in-xcode-b6027728003 but I keep getting this error on Xcode:
" 'opencv2/core.hpp' file not found "
I tried setting both Library Search Paths and Header Search Paths to recursive but it didn't change anything
I've also been getting this error on the terminal, I don't know if it's related. I think it's important to note that this isn't my first time trying to install opencv and I don't know if it's the old versions that keep messing with it. I tried to cleanup everything before installing this version but I'm not sure.
Undefined symbols for architecture x86_64:
"cv::namedWindow(cv::String const&, int)", referenced from:
_main in main-55ed98.o
"cv::String::deallocate()", referenced from:
cv::String::~String() in main-55ed98.o
cv::String::operator=(cv::String const&) in main-55ed98.o
"cv::String::allocate(unsigned long)", referenced from:
cv::String::String(char const*) in main-55ed98.o
"cv::imshow(cv::String const&, cv::_InputArray const&)", referenced from:
_main in main-55ed98.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Any suggestions on how to solve these issues please?

clang++ linker undefined symbols for architecture x86_64

$clang++ main.cpp -o out
Got following error, the same error happens when changing to g++. I have tested on some simple simple c++ code, the command works fine. So it the problem in that PNG class file? However, the same files worked on my MacOS before, but suddenly failed today.
Undefined symbols for architecture x86_64:
"PNG::writeToFile(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&)", referenced from:
_main in main-f6a06a.o
"PNG::PNG(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&)", referenced from:
_main in main-f6a06a.o
"PNG::PNG(unsigned long, unsigned long)", referenced from:
_main in main-f6a06a.o
"PNG::~PNG()", referenced from:
_main in main-f6a06a.o
"PNG::operator()(unsigned long, unsigned long)", referenced from:
_main in main-f6a06a.o
"PNG::width() const", referenced from:
_main in main-f6a06a.o
"PNG::height() const", referenced from:
_main in main-f6a06a.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Did you miss providing static/shared to the linker to resolve the linker errors for the methods mentioned? Also note that clang++ is a different compiler compared to g++ and hence need the static/shared libraries compiled prior by the same compiler you are using (clang++).
Try:
clang++ main.cpp -o out -lpng
Here's why: You are not providing the library that contains the implementation of your PNG library (libpng most likely). You need -lpng added to your compiler, so that it links with the relevant library. It may not be exactly -lpng in your particular case, but it's definitely a "missing library". Without knowing exactly what library you are trying to use (you didn't provide some source to "try the fix with").
As pointed out in the comment: you are using some kind of C++ wrapper on top, the above is probably not enough - but without knowing exactly which C++ wrapper on the png functionality you are actually using, it's hard to say what the command-line should look like.
Perhaps this

Undefined symbols for architecture x86_64: linking mistake?

I am new to cpp, want to have a implementation of particle filter, I try to run the code here https://github.com/NewProggie/Particle-Filter, which is a structured and easy understanding project. But when I try to compile and link:
g++ $(pkg-config --cflags --libs opencv) -I/usr/local/Cellar/opencv3/3.1.0_1/include -I /usr/local/Cellar/gsl/1.16/include -stdlib=libc++ main.cpp -o main
I have following linking problem:
Undefined symbols for architecture x86_64:
"colorFeatures::colorFeatures()", referenced from:
_main in main-2b4c23.o
"colorFeatures::~colorFeatures()", referenced from:
_main in main-2b4c23.o
"adaboostDetect::detectObject(_IplImage*, CvRect**)", referenced from:
_main in main-2b4c23.o
"adaboostDetect::adaboostDetect()", referenced from:
_main in main-2b4c23.o
"tracker::addObjects(_IplImage*, CvRect*, int)", referenced from:
_main in main-2b4c23.o
"tracker::initTracker(_IplImage*, CvRect*, int, int)", referenced from:
_main in main-2b4c23.o
"tracker::showResults(_IplImage*)", referenced from:
_main in main-2b4c23.o
"tracker::next(_IplImage*)", referenced from:
_main in main-2b4c23.o
"tracker::tracker()", referenced from:
_main in main-2b4c23.o
"tracker::~tracker()", referenced from:
_main in main-2b4c23.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Any kind person has ideas about this problem? Thanks in advance
have gsl installed properly
B) pass to g++ a reference to the lib directory where the gsl libraries are located (probably something like /usr/lib or /usr/local/lib, these should both be default locations for the linker to search), and also to where the header files are, and also tell the linker to do the linking.
g++ -o <name of executable> -L/path/to/gsl/libs -I/path/to/headers -lgsl <name of source file>
the -L tells it where to find the libraries (.so files on linux, .dylib on OS X), -I tells it where to find the headers, -l (that's a lower case L) tells it to link to the library, which would be named libgsl.so or libgsl.dylib.
First just try adding the -lgsl flag, then if it can't find libgsl.so (or .dylib), add the -L flag. NOTE: /path/to/gsl/libs and /path/to/headers are not what you should literally put in there, but replace them with the actual paths on your system.

libcurl issue when using D's std.net.curl on Mac

I'm trying to get up to speed using libcurl with D on Mac.
I'm using the latest dmd2 compiler (DMD64 D Compiler v2.062).
The following example compiles and works fine on Windows:
import std.net.curl, std.conv, std.stdio;
void main() {
string content = to!string(get("dlang.org"));
writeln(content);
}
When compiling it on Mac I get the following output:
~/src $ dmd dcurl.d
Undefined symbols for architecture x86_64:
"_curl_easy_cleanup", referenced from:
_D3std3net4curl4Curl8shutdownMFZv in libphobos2.a(curl_1522_37c.o)
"_curl_easy_duphandle", referenced from:
_D3std3net4curl4Curl3dupMFZS3std3net4curl4Curl in libphobos2.a(curl_151e_149.o)
"_curl_easy_init", referenced from:
_D3std3net4curl4Curl10initializeMFZv in libphobos2.a(curl_151d_432.o)
"_curl_easy_perform", referenced from:
_D3std3net4curl4Curl7performMFbZi in libphobos2.a(curl_1528_2fb.o)
"_curl_easy_setopt", referenced from:
_D3std3net4curl4Curl3setMFE3etc1c4curl10CurlOptionlZv in libphobos2.a(curl_1525_14c.o)
_D3std3net4curl4Curl3setMFE3etc1c4curl10CurlOptionAxaZv in libphobos2.a(curl_1524_14c.o)
_D3std3net4curl4Curl3setMFE3etc1c4curl10CurlOptionPvZv in libphobos2.a(curl_1526_14c.o)
_D3std3net4curl4Curl5clearMFE3etc1c4curl10CurlOptionZv in libphobos2.a(curl_1527_207.o)
"_curl_easy_strerror", referenced from:
_D3std3net4curl4Curl11errorStringMFiZAya in libphobos2.a(curl_1520_4a1.o)
"_curl_global_cleanup", referenced from:
_D3std3net4curl4Curl19_sharedStaticDtor29FZv in libphobos2.a(curl.o)
"_curl_global_init", referenced from:
_D3std3net4curl4Curl19_sharedStaticCtor28FZv in libphobos2.a(curl.o)
"_curl_slist_append", referenced from:
_D3std3net4curl3FTP3dupMFZS3std3net4curl3FTP in libphobos2.a(curl_1518_ea.o)
_D3std3net4curl3FTP10addCommandMFAxaZv in libphobos2.a(curl_1518_ea.o)
_D3std3net4curl4HTTP3dupMFZS3std3net4curl4HTTP in libphobos2.a(curl_1517_140.o)
_D3std3net4curl4HTTP16addRequestHeaderMFAxaAxaZv in libphobos2.a(curl_1517_140.o)
"_curl_slist_free_all", referenced from:
_D3std3net4curl3FTP4Impl6__dtorMFZv in libphobos2.a(curl_1518_ea.o)
_D3std3net4curl3FTP13clearCommandsMFZv in libphobos2.a(curl_1518_ea.o)
_D3std3net4curl4HTTP4Impl6__dtorMFZv in libphobos2.a(curl_1517_140.o)
_D3std3net4curl4HTTP19clearRequestHeadersMFZv in libphobos2.a(curl_1517_140.o)
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
--- errorlevel 1
Which seems to imply a linking issue.
I have libcurl at:
/usr/lib/libcurl.3.dylib /usr/lib/libcurl.4.dylib /usr/lib/libcurl.dylib
But I'm not even sure whether dmd is trying to use them.
I've done this before with C/C++ (on the same machine using these libraries) so I think it must be a versioning issue or else I need to pass some flags to the compiler.
Any help would be most appreciated.
You need to link against libcurl. It's not linked against by default. So, instead of
dmd dcurl.d
you need to do
dmd -L-lcurl dcurl.d

Poco C++ library on OSX 10.8.2: Undefined symbols for architecture x86_64

I'm trying to use Poco C++ library to do the simple http requests in C++ on Mac OS X 10.8.2. I installed Poco, copy-pasted the http_request.cc code from this tutorial, ran it with 'g++ -o http_get http_get.cc -lPocoNet', but got:
Undefined symbols for architecture x86_64:
"Poco::StreamCopier::copyStream(std::basic_istream<char, std::char_traits<char> >&, std::basic_ostream<char, std::char_traits<char> >&, unsigned long)", referenced from:
_main in ccKuZb1g.o
"Poco::URI::URI(char const*)", referenced from:
_main in ccKuZb1g.o
"Poco::URI::~URI()", referenced from:
_main in ccKuZb1g.o
"Poco::URI::getPathAndQuery() const", referenced from:
_main in ccKuZb1g.o
"Poco::URI::getPort() const", referenced from:
_main in ccKuZb1g.o
"Poco::Exception::displayText() const", referenced from:
_main in ccKuZb1g.o
"typeinfo for Poco::Exception", referenced from:
GCC_except_table1 in ccKuZb1g.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
Have been struggling with this for couple of hours. Any idea how to fix this? Thanks in advance!
the Poco::URI, Poco::StreamCopier classes are in the PocoFoundation library, so you will need to link to that library also.
g++ -o http_get http_get.cc -lPocoNet -lPocoFoundation
You don't appear to have specified the include path for the library and the library to use when compiling your source.
You need to provide the -I and the -L directive to g++ to specify the include path for the library and the library itself respsectively.