Please need the urgent support, i am student and programming C++ using xcode 11
getting following error
#include <iostream> . 'iostream' file not found
Xcode is collosal overhead to just to compile a command-line C++ program. Once you have Xcode 11 installed, and have agreed to the extra download dialog, install the Xcode command-line tools:
xcode-select --install
Now, you will have access to clang++ on the command-line and by default, it knows to load the libC++ library if you are not doing any of the later standards (c++17).
To compile the following:
// memoized version of Fibonacci sequence
// Prior results are stored/searched to avoid expensive recalculations
// More: http://xlinux.nist.gov/dads/HTML/memoize.html
// see man clang
// clang++ -Wall -O2 -o fib_memo fib_memo.C -std=c++2a
#include <iostream>
#include <locale>
#include <map>
using namespace std;
// key/value pair associative array
std::map<u_long, u_long> alreadyknown;
u_long n=0, newvalue=0;
u_long fib(u_long n) {
// true if we reach end of array without find success
if (alreadyknown.find(n) == alreadyknown.end()) {
newvalue = fib(n-1) + fib(n-2);
alreadyknown[n] = newvalue;
}
return alreadyknown[n];
}
int main(int argc, char* argv[]) {
// initialize memoization key/value pair
alreadyknown[0] = 0;
alreadyknown[1] = 1;
cout<<"Enter the number of terms: ";
cin>>n;
std::locale mylocale("");
std::cout.imbue(mylocale); // use locale number formatting style
cout<<fib(n) << endl;
return 0;
}
Now, using the default C++ library and specifying the iso C++ 2017 spec with amendments and GNU extensions:
clang++ -Wall -O2 -o fib_memo fib_memo.C -std=c++2a
and:
fib_memo
Enter number of terms: 50
12,586,269,025
Same with my Xcode. I tried to reinstall Catalina and Xcode but it didn't help.
Same thing is happening here. I do have Homebrew installed though as well.
Anyone experiencing the same issue and does not have homebrew installed?
I'm getting this same problem as well and I am not using homebrew.
Having the same problem since upgraded to Catalina. And the C++ program can actually run in Xcode though the warning is there.
Doesn't work for me.
That is exactly what is happening in my case as well.
how to Update Command Line Tool from Software Update?
When you create a new project in Xcode, you need to use the correct project template. In this case, the template would be a “Command line tool”. Next, you will need to pick the correct language, C++. That will setup the correct include paths and libraries to support C++.
Once again reinstalled Xcode. Issue went away but creating a new file caused it to return for some reason. Really not sure what it could be. Maybe its a bug. I deleted all the Xcode files, reinstalled from the App Store and still same issue.
Please do not delete any installed files. There is no way that having too many files for the same purpose can result in a “file not found” error. Most likely, it was xcode-select that caused your problem. It may have also been a factor for other people if they had used xcode-select and then tried to use a different version of Xcode, after having used a beta, for example.
Have you mucked around with the system? Like moving or deleting files?
You might want to re-install XCode, but it should just work, like etresoft said.
brew update
Worked for me. Nothing else helped.
After reinstall from "App Store", this issue never appears again for me. It lived through a coupe days of OPENGL without that error. Did you reinstalled the website Xcode?
I updated my mac today and the issue seems to be gone. I'll make sore to report any future error. Try updating it too, maybe it will sole the problem for you too.
You’re right.
Getting error on Xcode 11 when programming on C++