I have imported the ffmpeg and SDL libraries into my Xcode project for a Cocoa application.
My project builds and runs successfully with these libraries when my project contains only Cocoa classes, but when I include a C file in my project, the build fails with one warning and 35 errors:
The warning is:
ld: warning: in /Developer/SDKs/MacOSX10.6.sdk/usr/lib/gcc/powerpc-apple-darwin10/4.2.1/libgcc.a, file was built for unsupported file format which is not the architecture being linked (x86_64)
and the errors:
"___gedf2", referenced from:
_eval_expr in libavcodec.a(eval.o)
_quantize_lpc_coefs in libavcodec.a(lpc.o)
_rc_2pass2_before in libxvidcore.a(plugin_2pass2.o)
"___ledf2", referenced from:
_qp2bits in libavcodec.a(ratecontrol.o)
_get_qscale in libavcodec.a(ratecontrol.o)
"___umodsi3", referenced from:
_vorbis_parse_setup_hdr_codebooks in libavcodec.a(vorbis_dec.o)
_vorbis_parse_setup_hdr_codebooks in libavcodec.a(vorbis_dec.o)
For running the code, these are the configuration settings:
Active architecture: x86_64
Architecture in project setting: Standard (32/64_bit universal)
Mac OS X version: 10.6.3
Xcode version: 3.2.3
Also, the same code is building and running successfully with the same settings on my other system, a Mac Mini.
If anyone has any idea what I am missing then please help. Thanks.
Read the error message carefully (emphasis mine):
ld: warning: in /Developer/SDKs/MacOSX10.6.sdk/usr/lib/gcc/powerpc-apple-darwin10/4.2.1/libgcc.a, file was built for unsupported file format which is not the architecture being linked (x86_64)
Looks like you're mixing PowerPC and Intel libraries somehow. You're compiling for x86_64 but you're picking up a libgcc.a for PowerPC.
Those symbols with all the leading underscores are probably supposed to come from libgcc.a but you're not linking the x86_64 version of libgcc.a so they're missing in action and chaos ensues. Sounds like something in your xcode configuration is confused.
Related
It is definitely possible to target Intel when compiling on an Apple Silicon (ARM64) system, as Xcode does that all the time when building universal bundles of an app. However, I am unable to replicate this compiling a C program with make (specifically Stockfish).
What I've tried
I'm invoking make like so: make build ARCH=x86-64-modern COMP=clang (the same command works when I substitute x86-64-modern for apple-silicon). I've tried using the gcc compiler, which also worked when targeting the apple-silicon arch.
The problem
The make build command terminates with a bunch of errors, most importantly:
Undefined symbols for architecture x86_64:
"_main", referenced from:
implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Above the error is a bunch of lines complaining that a file was built for an "unknown bitcode architecture:
ld: warning: ignoring file <name>.o, lto file was built for unknown bitcode architecture which is not the architecture being linked (x86_64): <name>.o
So, it seems like the compilation phase succeeds, but the linking phase fails due to missing symbols. How would I acquire and provide the missing symbols to ld such that it can link successfully?
What I am trying to do is take a bunch of .C files that I created using f2c.exe on a Windows computer and use them in Xcode in an already existing project consisting primarily of Swift code.
On my Windows computer I used f2c to generate the .C files and then was able to build them to an executable and it runs as expected. So I took all of the .C files and brought them to my Xcode project and that is where I am currently stuck.
I only just added in the .C files and Xcode gives the following errors when I try to buid:
Undefined symbols for architecture arm64:
"_s_wsle", referenced from:
_xplannr_ in X1.o
...
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
X1.C is one of the .C files I have as an example. Additionally there are many repeated messages, I have just shown 1 for the purpose of this question. They all follow the same format as what I have provided here.
So what I am trying to understand is, what does the error message that is being provided indicating? Is this an issue of how the .C files were generated, or some configuration issue within Xcode that is not correct? Any ideas are appreciated.
So I am learning OpenGL 4 from openglbook.
I copied and pasted the simple window creating program in my editor and followed Compiling OpenGL programs on OS X by using
gcc -o hello hello.c -framework OpenGL -framework GLUT
I got the following error:
Undefined symbols for architecture x86_64:
"_glewGetErrorString", referenced from:
_Initialize in chapter-c8ba2d.o
"_glewInit", referenced from:
_Initialize in chapter-c8ba2d.o
"_glutInitContextFlags", referenced from:
_InitWindow in chapter-c8ba2d.o
"_glutInitContextProfile", referenced from:
_InitWindow in chapter-c8ba2d.o
"_glutInitContextVersion", referenced from:
_InitWindow in chapter-c8ba2d.o
"_glutSetOption", referenced from:
_InitWindow in chapter-c8ba2d.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
If I understand correctly, the problem is tha -framework GLUT means that you're linking against the GLUT framework shipped by Apple with macOS and located inside /System/Library/Frameworks folder. This GLUT implementation unfortunately lacks some functionality provided by current version of FreeGLUT. And OpenGLBook.com tutorials use some of this functionality, thus, as it is mentioned many times here, the code examples have to be compiled with FreeGLUT.
There are, of course, few ways this can be done. The easiest one is by installing freeglut by means of the infamous Homebrew package manager and then setting up the CMake project as described below.
So, first install freeglut
brew install freeglut
Then setup CMake project by adding the following lines into CMakeLists.txt
find_package(FreeGLUT CONFIG REQUIRED)
find_package(glew CONFIG REQUIRED)
link_libraries(FreeGLUT::freeglut GLEW::GLEW)
I am trying to compile a mex file that requires the mpfr C library, using MATLAB R2013a on Mac OS 10.8.5. I would like it to run on systems that don't have a separate installation of MPFR, so I am trying to include the static library:
mex my_program.c libmpfr.a
I copied the libmpfr.a library into the folder with my source code to simplify things. When I run this command I get the following error message:
ld: targeted OS version does not support use of thread local variables in _mpfr_add for architecture x86_64
A little research suggested that this issue could be due to a problem with the llvm-gcc-4.2 compiler that comes with Xcode and is used in MATLAB by default. So, I tried to set up a different compiler. I got GCC 4.7.4 (the latest version supported by MATLAB) from MacPorts, as described here: http://www.ficksworkshop.com/blog/14-coding/65-installing-gcc-on-mac. Next, I edited the mexopts.sh file to point MATLAB to the correct compiler, by entering the following settings:
CC='/opt/local/bin/gcc-mp-4.7'
CXX='/opt/local/bin/g++-mp-4.7'
Now when I try to compile, I get a different error message:
In file included from /Applications/MATLAB_R2013a.app/extern/include/matrix.h:294:0,
from /Applications/MATLAB_R2013a.app/extern/include/mex.h:58,
from include/main.h:5,
from include/poisson.h:7,
from src/main.c:22:
/Applications/MATLAB_R2013a.app/extern/include/tmwtypes.h:61:21: fatal error: float.h: No such file or directory
If, in mexopts.sh, I additionally set
SDKROOT='/opt/local/'
or a number of other choices (based on the locations of different copies of float.h that I can find on my system), I instead see
my_program.c:10:20: fatal error: stdlib.h: No such file or directory
So it seems that GCC-MP-4.7 is having trouble locating all of the standard C libraries.
I'd be grateful for a solution to either of these issues (linking to static mpfr useing the default compiler, or configuring GCC 4.7 to find the standard C libraries).
I found that the "thread local variables" error was caused by the compiler trying to include backwards-compatibility to OSX 10.5. Since I don't need it to do this, I edited the mexopts.sh file, replacing this line
MACOSX_DEPLOYMENT_TARGET='10.5'
with this:
MACOSX_DEPLOYMENT_TARGET='10.8'
This resulted in the mex file compiling successfully using the built-in Xcode compiler.
I'm trying to add a C library to Xcode. I downloaded the library from an online C class, and the zipped file contains two files: cs50.c and cs50.h.
I installed these files using the following commands:
gcc -c -ggdb -std=c99 cs50.c -o cs50.o
ar rcs libcs50.a cs50.o
rm -f cs50.o
chmod 0644 cs50.h libcs50.a
sudo mv cs50.h /usr/include
sudo cp libcs50.a /usr/lib
When building the project, I get the following error message:
Undefined symbols for architecture x86_64:
"_GetString", 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)
This is how I'm referencing the header file in my program:
#include </usr/include/cs50.h>
If I don't include the path, I get a can't find file message.
My version of Xcode is: Version 4.5.2 (4G2008a) and I'm running OS X 10.7.5.
Thanks for any suggestions.
Update:
As a general rule, you should never install or modify anything in /usr unless you have a very good reason to do so. This directory is reserved for the operating system, and you can quickly run into a lot of problems - for instance if you accidentally overwrite a system library or header file and even installing new things in there may cause problems when updating your operating system.
If you really need to install this system-wide, then put it into /usr/local.
However, since you compiled the library with debugging information, I assume that you also want to test and play around with it in your project.
To do that, it's much easier to add the sources as a new "C/C++ Library" target to your project. Then Xcode will take care of all the ugly details such as compiling, choosing the right processor architecture (32 or 64 bit), you'll get source-level debugging support in Xcode and if you ever want to install your app or create a package for it, then Xcode will also automatically bundle the dependencies for you.
If you trying to use gcc to compile the cs50.h library, I have found that to be unsuccessful on most modern 64 bit macs. Xcode 4.x generally wants a 64 bit compatible library format. GCC has not been updated to include 64 bit object files. Clang/LLVM is a rising alternative to gcc, and is used by Apple for Xcode as their preferred compiler engine. I have not personally tried it yet, but will be exploring Xcode to produce a compatible library for Xcode. I am taking the Harvardx cs50x course at edX, and it is great course, even for experienced programmers. The cs50.h library is interesting, because it provides relatively robust I/O routines for various variable types, e.g. String, Integer. float for the c programming language, including good protection for buffer overflow attacks.
You are actually building a custom dynamic library to be added to Xcode, which is also known as a framework. If you have apple developer account, check out the framework programming guide, it should prove useful.