I am a newbie to Objective C programs. I'm learning to code from tutorialspoint.com
As mentioned therein I downloaded GNUstep (Windows).
First, installed the MSYS/MinGW System package and then core package.
After that followed the steps mentioned there. I created a simple program with name hello.m and Stored that in C drive (Snapshot 1)
I don't know the meaning of this command below but entered it:
$ gcc gnustep-config --objc-flags -L /GNUstep/System/Library/Libraries hello.m -o hello -lgnustep-base -lobjc
The error it shows is - sh: gcc: command not found
Please help with the same, to compile and run my first Objective C program
gcc is the compiler, the other parameters are for compiling objective-c code.
Apparently you have misconfiguration in MSYS/MinGW setup.
Check out following post which has alternative and easier solution for running gcc under Windows.
Related
In my makefile I have:
g++ -o Out Out.o -I Headers_Directory -L Libraries_Directory -lFile1 -lFile2
In my Libraries_Directory I have two files libFile1.a and libFile2.so
ld finds libFile1.a but cannot find libFile2.so. How that is possible and how can I resolve the issue?
I am compiling in Cygwin and using GNU gcc-g++ compiler.
A minimalist that regenerates the error:
Download the Linux Version of Gurobi here. Then, install the software using this instruction. You need to activate the software by obtaining a license from here. Free academic license for research purpose is available. Finally navigate to the following folder
installation_directory/gurobi701/linux64/examples/build
and issue the command make. You have to compile on Cygwin with GNU gcc-g++ compiler.
I am trying to compile a simple hello world program written in objective c from ubuntu but I am getting an error as
gcc: error: unrecognized command line option ‘-fobjc-nonfragile-abi’
To compile I am using the command
gcc gnustep-config --objc-flags -lgnustep-base hello.m -o hello
Can you please help me out with this. I am not getting any solution in google too.
The best way to compile gnustep code is with makefiles. It avoids all this faff with GCC:
make a file called GNUmakefile
Make the content:
include $(GNUSTEP_MAKEFILES)/common.make
TOOL_NAME=hello
hello_OBJC_FILES=hello.m
include $(GNUSTEP_MAKEFILES)/tool.make
just type:
make
to compile, the output is in the obj/ dir
I would give this a read
http://www.gnustep.it/nicola/Tutorials/WritingMakefiles/
Now a problem I always have is it can't find the gnustep makefiles.
The long term fix is to add it to path, the quick fix is every session, type:
export GNUSTEP_MAKEFILES=/usr/share/GNUstep/Makefiles
/usr/share/GNUstep/Makefiles is my gnustep makefile dir, YOURS MAY BE DIFFERENT! but I assume that this is the dir if you installed gnustep like this:
apt-get install gnustep gnustep-devel
it may be worth making sure you have the gnustep-devel package!
Good luck!
I'm learning Objective-C language. Since I don't have a Mac, I'm compiling and running my code within Ubuntu 11.04 platform.
Until now, I was using gcc to compile. I've installed GNUStep and all was working. But then I started to try some Objective-C 2.0 features, like #property and #synthesize, that gcc does not allow.
So I tried to compile the code with Clang, but it seems that it is not correctly linking my code with the GNUStep libraries, not even with a simple Hello world program.
For example, if I compile the following code:
#import <Foundation/Foundation.h>
int main(void) {
NSLog(#"Hello world!");
return 0;
}
The output of the compiler is:
/tmp/cc-dHZIp1.o: In function `main':
test.m:(.text+0x1f): undefined reference to `NSLog'
/tmp/cc-dHZIp1.o: In function `.objc_load_function':
test.m:(.text+0x3c): undefined reference to `__objc_exec_class'
collect2: ld returned 1 exit status
clang: error: linker (via gcc) command failed with exit code 1 (use -v to see invocation)
The command I'm using to compile is
clang -I /usr/include/GNUstep/ test.m -o test
with the -I directive to include the GNUStep libraries (otherwise, Clang is not able to find Foundation.h).
I've googled my problem, and visited both GNUStep and Clang web pages, but I haven't found a solution to it. So any help will be appreciated.
Thanks!
The problem was that the library gnustep-base was not being used by the linker. So the solution to this was using the option -Xlinker, that sends arguments to the linker used by clang:
clang -I /usr/include/GNUstep/ -Xlinker -lgnustep-base test.m -o test
The statement "-X linker -lgnustep-base" made the magic. However, I had problems with this command related to the class that represents a string in Objective-C:
./test: Uncaught exception NSInvalidArgumentException, reason: GSFFIInvocation:
Class 'NXConstantString'(instance) does not respond to forwardInvocation: for
'hasSuffix:'
I could solve it adding the argument "-fconstant-string-class=NSConstantString":
clang -I /usr/include/GNUstep/ -fconstant-string-class=NSConstantString \
-Xlinker -lgnustep-base test.m -o test
In addition, I've tried with some Objective-C 2.0 pieces of code and it seems to work.
Thank you for the help!
You can try gcc compiler:
First of all install GNU Objective-C Runtime: sudo apt-get install gobjc
then compile: gcc -o hello hello.m -Wall -lobjc
You are not able to use ObjC 2.0 features because you're missing a ObjC-runtime supporting those. GCC's runtime is old and outdated, it doesn't support ObjC 2.0. Clang/LLVM doesn't have a acompanied runtime, you need to install the ObjC2-runtime from GNUstep (which can be found here: https://github.com/gnustep/libobjc2 ) and reinstall GNUstep using this runtime.
Here are some bash scripts for different Ubuntu versions, that do everything for you:
http://wiki.gnustep.org/index.php/GNUstep_under_Ubuntu_Linux
And please don't try to reinvent GNUstep make, instead, use it:
http://www.gnustep.org/resources/documentation/Developer/Make/Manual/gnustep-make_1.html
If you really don't think so, here is some excerpt from there:
1.2 Structure of a Makefile
Here is an example makefile (named GNUmakefile to emphasis the fact that it relies on special features of the GNU make program).
#
# An example GNUmakefile
#
# Include the common variables defined by the Makefile Package
include $(GNUSTEP_MAKEFILES)/common.make
# Build a simple Objective-C program
TOOL_NAME = simple
# The Objective-C files to compile
simple_OBJC_FILES = simple.m
-include GNUmakefile.preamble
# Include in the rules for making GNUstep command-line programs
include $(GNUSTEP_MAKEFILES)/tool.make
-include GNUmakefile.postamble
This is all that is necessary to define the project.
In your case replace all occurrences of simple with test and you're done
1.3 Running Make
Normally to compile a package which uses the Makefile Package it is purely a matter of typing make from the top-level directory of the package, and the package is compiled without any additional interaction.
I was just starting to study obj-c on Ubuntu Linux today, the tutorial that I followed is http://www.otierney.net/objective-c.html, when I typed in the code that requires for Foundation/NSObject.h, the error appeared:
Fraction.h:1: fatal error: Foundation/NSObject.h: No such file or directory
and i searched for the solutions, and found a proper one
gcc -o Fraction -I/usr/GNUstep/System/Library/Headers
-L/usr/GNUstep/System/Library/Libraries
Fraction.m
-ldl
-lobjc
I tried this, but I found that I cannot find Headers under the Library directory. (My folder of GNUstep is /usr/share/GNUstep).
Does anyone know how to achieve the Headers?
I installed all the dev packages related to GNUstep but still no luck.
Hope I state my question clear enough. Sorry for my English.
Try with gnustep-config
gcc `gnustep-config --objc-flags` \
`gnustep-config --objc-libs` Fraction.m -o Fraction
GNUStep uses a fairly involved set of gmake macros - I wouldn't expect a simple command-line invocation of gcc to work very well, although to be honest I haven't tried that way myself. I found Nicolo Pera's tutorial and the project's own reference page to be quite useful when learning how to write make files for use with GNUStep.
In my case, compiling SOPE on CentOS 7, installed
yum install gnustep-base-devel
This solved the problem.
In my case, I installed gnustep-base to fix this error:
yum install gnustep-base
When I compiled an Objective-C code on Windows, I got this error.
$ gcc -o abc main.m
In file included from MyClass.m:2,
from main.m:2:
myclass.h:1:32: Foundation/NSObject.h: No such file or directory
In file included from MyClass.m:2,
from main.m:2:
myclass.h:4: error: syntax error before '(' token
myclass.h:6: error: cannot find interface declaration for `NSObject', superclass of `myclass'
Why is that? How can I fix this?
Thanks to initiate my help dear frnds
i hv just got the answer after posting this question. so the command to compile in window environment is this..
gcc `gnustep-config --objc-flags` -o myf main.m -L /GNUstep/System/Library/Libraries -lobjc -lgnustep-base
thanks for all.
You say you're on Windows. Do you in fact have an environment (such as GNUstep or Cocotron) that would give you the Foundation framework installed and set up correctly? Because I would guess not, and not having Foundation would indeed lead to errors about not having Foundation.