I had a question on setting up GMP Library to work on XCode for C++ programming. Although I have tried pursuing the GMP manual and also other similar stack questions on getting the library to work properly, I still have not been able to properly get the library to work. I am new to C++ and programming in general so please bear with me.
Things I have tried:
Install GMP library through homebrew using brew install gmp
Using the XCode interface under header search paths and library search paths added the path "/usr/local/include" (this is where homebrew installs the gmp library)
Under other linker flags added -lgmp -lgmpxx
Tried running various sample codes e.g.
#include <iostream>
#include <stdio.h>
#include <gmp.h>
#include <gmpxx.h>
using namespace std;
int main ()
{
mpz_t p;
mpz_init(p);
return 0;
}
However this code fails to compile and the XCode debugger has the following error messages:
Undefined symbols for architecture x86_64:
"___gmpz_init", 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)
Thanks!
Related
I am new to programming and wanted to setup c++ on my MacBook Air M1 running on macOS Monterey. I followed some online tutorials to download Homebrew, Mingw-64(using Homebrew) and finally installed VS Code and then installed the c++ extension pack and code-runner extension.
However when I tried to run the following code:
#include <iostream>
using namespace std;
int main(){
cout << "helloworld" << endl;
return 0;
}
I got the following error:
Undefined symbols for architecture arm64:
"_main", referenced from:
implicit entry/start for main executable
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Can somebody please help me out?
I'm trying to use the fmt (https://github.com/fmtlib/fmt) formatting header library in my c++ project.
I've added the path to the core header file at the top of my main file like so:
#include "../third_party/fmt/core.h"
but when I try to call any function like:
string message = fmt::format("The answer is {}", 42);
I get the following error:
Undefined symbols for architecture x86_64:
"std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > fmt::v5::internal::vformat<char>(fmt::v5::basic_string_view<char>, fmt::v5::basic_format_args<fmt::v5::buffer_context<char>::type>)", referenced from:
std::__1::basic_string<std::__1::enable_if<internal::is_string<char [17]>::value, fmt::v5::internal::char_t<char [17]>::type>::type, std::__1::char_traits<std::__1::enable_if<internal::is_string<char [17]>::value, fmt::v5::internal::char_t<char [17]>::type>::type>, std::__1::allocator<std::__1::enable_if<internal::is_string<char [17]>::value, fmt::v5::internal::char_t<char [17]>::type>::type> > fmt::v5::format<char [17], int>(char const (&) [17], int const&) in main.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)
make[2]: *** [main] Error 1
make[1]: *** [CMakeFiles/main.dir/all] Error 2
make: *** [all] Error 2
I'm not sure how to use this as this is how I have used other header libraries in the past such as cxxopts. Any help would be appreciated!
You should link with the fmt library or use the optional header-only mode.
For example, if you have the file test.cc:
#include <fmt/core.h>
int main() {
fmt::print("The answer is {}.", 42);
}
You can compile and link it with gcc:
g++ -std=c++11 test.cc -lfmt
From a comment in #vitaut's answer, if you change your #include line from this:
#include "../third_party/fmt/core.h"
to this:
#include "../third_party/fmt/format.h"
it will cause the code to be compiled in "header-only mode", and you won't need to change your build process to compile and link in the {fmt} library.
I'm working on Mac, and I did not realize that you can install the library using brew. It appears at the end of the page. I have been dealing with symbol errors all evening, and I'm not sure that all my problems were related to the build process. The compiling process was also not working properly.
The paths where the library is installed are: /usr/local/include and /usr/local/lib.
I'm using g++-11 to build my project and this instruction works for me:
g++-11 -std=c++20 -I/usr/local/include -L/usr/local/lib -lfmt main.cpp -o main
The only problem is that it works partially. It works fine with print:
fmt::print("Don't {}!\n", "panic");
But it breaks using format:
fmt::format("Don't {}!\n", "panic");
I'm missing something, but I'm not sure what.
By the way, if you are using VSCode, you can create a c_cpp_properties.json into your .vscode folder and add the include path for the headers.
{
"includePath": [
[...],
"/usr/local/include/"
],
}
Not sure if this is related to your case, but I hope it helps.
I've been trying for hours to get Boost C++ libraries working on MacOS 10.13.6.
I'm up-to-date with Xcode and Homebrew.
I used brew install boost to install boost and followed the Boost Getting Started instructions for help with compiling.
I've tried everything that I can think of and read every post I can find on StackOverflow about this.
I'm attempting to compile with:
g++ -std=c++17 -stdlib=libc++ -I /usr/local/opt/boost/include -L /usr/local/opt/boost/lib ass3.cpp -o ass3 -lboost_filesystem
and I get the following error message:
Undefined symbols for architecture x86_64: "boost::system::detail::generic_category_ncx()", referenced from: boost::system::generic_category()
in ass3-3dc386.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
I haven't yet tried to install Boost from source.
If I exclude -std=c++17 the code will compile with a warning that I am using c++11 alias. As I get further into my project I'll be using c++17 specific features so I need to include this as far I as I know.
Compiler warning:
warning: alias declarations are a C++11 extension [-Wc++11-extensions]
What am I missing?
How can I include Lua in my project in Xcode?
I have installed Lua via the instructions on the website (curl, extract, make macosx install, etc).
I can reference lua
extern "C" {
#include "lua.h"
#include "lualib.h"
#include "lauxlib.h"
}
But when I go to use it, I get an error (even writing something as simple as the following)
lua_State *L = luaL_newstate();
lua_close(L);
It tells me :
Undefined symbols for architecture x86_64:
"_luaL_newstate", referenced from:
_main in main.o
"_lua_close", 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)
Any advice would be much appreciated. If you need further information, let me know and I can edit it in. Thanks!
EDIT:
Added the -llua flag (SFML included the /usr/local/lib and include). Now getting "ignoring file /usr/local/lib/liblua.a, file was built for archive which is not the architecture being linked (i386): /usr/local/lib/liblua.a"
EDIT2:
I changed Base SDK to Latest OS X (OS X 10.9) and Build Active Architecture Only to "Yes" and now it will compile.
In Xcode, select < ProjectName > with blue icon on top of the left pane (where all the sources are), then in main window select a target under Targets. In Build Settings tab, select All instead of Basic and set following parameters:
Other Linker Flags = -llua
Header Search Paths = /usr/local/include
Library Search Paths = /usr/local/lib
Assuming Lua headers were installed in /usr/local/include, and liblua.a in /usr/local/lib.
You may also use search field to find them.
I am attempting to build a very simple command line application, in Xcode, that will print out basic information about MXF video files. In order to do this I need to use the libmxf, libbmx, and libbmx libraries available for download here:
http://sourceforge.net/p/bmxlib/home/Home/
My C++ code is incredibly simple at this point:
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cerrno>
#include <vector>
#include <bmx/mxf_reader/MXFFileReader.h>
#include <bmx/mxf_reader/MXFGroupReader.h>
#include <bmx/mxf_reader/MXFSequenceReader.h>
#include <bmx/mxf_reader/MXFFrameMetadata.h>
#include <bmx/MXFUtils.h>
#include <bmx/Utils.h>
using namespace std;
using namespace bmx;
#define MXF_OPEN_READ(fn, pf) mxf_disk_file_open_read(fn, pf)
int main(int argc, const char * argv[])
{
std::vector<const char *> filenames;
std::cout << "mxfheader: execution beginning...\n";
for (int cmdln_index = 0; cmdln_index < argc; cmdln_index++) {
if (!check_file_exists(argv[cmdln_index])) {
if (argv[cmdln_index][0] == '-') {
fprintf(stderr, "Unknown argument '%s'\n", argv[cmdln_index]);
} else {
fprintf(stderr, "Failed to open input filename '%s'\n", argv[cmdln_index]);
}
return 1;
}
filenames.push_back(argv[cmdln_index]);
}
std::cout << filenames[0] << "\n";
return 0;
}
When I compiled the BMX library, I was sure to run configure with 64-bit support, like so:
./configure --build=x86_64-apple-darwin11.4.2 --host=x86_64-apple-darwin11.4.2 CFLAGS="-arch x86_64" CXXFLAGS="-arch x86_64" LDFLAGS="-arch x86_64" CC=clang CXX=clang++
In the XCode Project under Build Settings, I have added /usr/local/lib to my Search Paths. Under Build Phases, I have added "libbmx-0.1.3.dylib", "libMXF-1.0.4.dylib", and "libMXF++-1.0.4.dylib" to the "Link Binary With Libraries" section.
I have verified that these libraries are, indeed, 64-bit ( file libbmx-0.1.3.dylib returns libbmx-0.1.3.dylib: Mach-O 64-bit dynamically linked shared library x86_64 ).
Every time I try and build the application, I get the following linker error:
Ld /Users/ned/Library/Developer/Xcode/DerivedData/mxfheader-bkwawmplsoqpdadfxartceqkbolo/Build/Products/Debug/mxfheader normal x86_64
cd /Users/ned/Documents/src/mxfheader
setenv MACOSX_DEPLOYMENT_TARGET 10.7
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk -L/Users/ned/Library/Developer/Xcode/DerivedData/mxfheader-bkwawmplsoqpdadfxartceqkbolo/Build/Products/Debug -L/usr/local/lib -F/Users/ned/Library/Developer/Xcode/DerivedData/mxfheader-bkwawmplsoqpdadfxartceqkbolo/Build/Products/Debug -filelist /Users/ned/Library/Developer/Xcode/DerivedData/mxfheader-bkwawmplsoqpdadfxartceqkbolo/Build/Intermediates/mxfheader.build/Debug/mxfheader.build/Objects-normal/x86_64/mxfheader.LinkFileList -mmacosx-version-min=10.7 -stdlib=libc++ -lbmx-0.1.3 -lMXF-1.0.4 -lMXF++-1.0.4 -o /Users/ned/Library/Developer/Xcode/DerivedData/mxfheader-bkwawmplsoqpdadfxartceqkbolo/Build/Products/Debug/mxfheader
Undefined symbols for architecture x86_64:
"bmx::check_file_exists(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >)", 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)
Any help would be appreciated. Thanks!
Your problem is the option: -stdlib=libc++ in the command line. It's causing a link to the wrong libc++, you need to make it -stdlib=libstdc++, as this is the stdlib that the libbmx library is compiled against.
under the Apple LLVM compiler options for the C++ standard library, select: libstdc++, or pick compiler default (which should choose libstdc++ also)