SFML "undefined reference to `sf::Font::loadFromFile()' " - c++

Question

I'm learning how to use SFML, and after completing the RenderWindow tutorial with no problems, I've begun trying to use sf::Text and sf::Font with the next tutorial on the page.
Here is my code:
#include <iostream>
#include <SFML/Graphics.hpp>
#include <SFML/Graphics/Font.hpp>
#include <SFML/Graphics/Text.hpp>
int main() {
// initialise font
sf::Font ubuntu_r;
if(!ubuntu_r.loadFromFile("Ubuntu-R.ttf")) {
// unable to load font
std::cout << "Cannot load font." << std::endl;
}
// initialise text
sf::Text text;
text.setFont(ubuntu_r);
text.setString("Hello, world!");
text.setCharacterSize(50);
text.setColor(sf::Color(0x555555ff));
// initialise window
sf::RenderWindow win(sf::VideoMode(800,600),"Hello, world!");
// main loop
while(win.isOpen()) {
// check for closure
sf::Event e;
while(win.pollEvent(e)) {
if(e.type == sf::Event::Closed) {
win.close();
}
}
// draw text to screen
win.clear(sf::Color::White);
win.draw(text);
win.display();
}
return 0;
}
resulting in the following on compile:
$ g++ -c text.cpp
$ g++ text.o -o text -lsfml-graphics -lsfml-system -lsfml-window
text.o: In function `main':
text.cpp:(.text+0x10d): undefined reference to `sf::Font::loadFromFile(std::string const&)'
collect2: error: ld returned 1 exit status
This is very confusing, as I've checked in Font.hpp and loadFromFile() is definitely defined.
Commenting out all the text and font related code results in a perfectly compiled program that creates a white window that closes normally.
Probably the weirdest thing of all, however, is that if I selectively comment just the loadFromFile() bit:
#include <iostream>
#include <SFML/Graphics.hpp>
#include <SFML/Graphics/Font.hpp>
#include <SFML/Graphics/Text.hpp>
int main() {
// initialise font
sf::Font ubuntu_r;
/*
if(!ubuntu_r.loadFromFile("Ubuntu-R.ttf")) {
// unable to load font
std::cout << "Cannot load font." << std::endl;
}
*/
// initialise text
sf::Text text;
text.setFont(ubuntu_r);
text.setString("Hello, world!");
text.setCharacterSize(50);
text.setColor(sf::Color(0x555555ff));
// initialise window
sf::RenderWindow win(sf::VideoMode(800,600),"Hello, world!");
// main loop
while(win.isOpen()) {
// check for closure
sf::Event e;
while(win.pollEvent(e)) {
if(e.type == sf::Event::Closed) {
win.close();
}
}
// draw text to screen
win.clear(sf::Color::White);
//win.draw(text);
win.display();
}
return 0;
}
this program compiles, runs with a white screen as before, but gives a segfault on close!
$ g++ -c text.cpp
$ g++ text.o -o text -lsfml-window -lsfml-system -lsfml-graphics
$ ./text
(I click close on the window)
Segmentation fault (core dumped)
What on earth is going on? Clearly the sf::Font isn't a problem as it compiles and runs fine with everything except loadFromFile().
I'm unsure about the segfault, because on this post the problems seem ever so slightly different to my own (it doesn't occur every time, for example). My initial thought is that the segfault is caused by the program trying to draw with an undefined font, but shouldn't that result in a runtime error as soon as the program is launched, and not only on closing the window?
Also, could this be related to this problem? My error message looks pretty different.
I'm using Ubuntu 16.04, compiling with gcc in terminal and writing the code in jEdit.