error sfml

[green rivet]

When your question is answered use !solved to mark the question as resolved.

Remember to ask specific questions, provide necessary details, and reduce your question to its simplest form. For tips on how to ask a good question use !howto ask.

[wild sequoia]

@full nebula

/usr/bin/ld: main.o: in function `main':
main.cpp:(.text+0x11): undefined reference to `Game::Game()'
/usr/bin/ld: main.cpp:(.text+0x1f): undefined reference to `Game::update()'
/usr/bin/ld: main.cpp:(.text+0x2b): undefined reference to `Game::render()'
/usr/bin/ld: main.cpp:(.text+0x37): undefined reference to `Game::running() const'
/usr/bin/ld: main.cpp:(.text+0x4c): undefined reference to `Game::~Game()'
/usr/bin/ld: main.cpp:(.text+0x5f): undefined reference to `Game::~Game()'
collect2: error: ld returned 1 exit status

error message

[full nebula]

who wrote the makefile

[wild sequoia]

i found it on the internet

[full nebula]

you're on linux?

[wild sequoia]

yes

[full nebula]

follow this

https://www.sfml-dev.org/tutorials/3.0/getting-started/cmake/

[wispy wren]

your game.cpp file did not define ~Game(), Game::running() and all of the rest of these functions

[wispy wren]

it's not the cmake script that is causing the issue

[wild sequoia]

How can I fix the problem

[wispy wren]

wait, something else is happening here

your game.cpp file has these implementations, but when the raw binary sfml-app is built, more specifically linked, it behaves as if game.cpp has never been compiled at all.

I think I noticed what happened here. your makefile doesn't have a line there, or "recipe" to "cook" the file game.o, compiled from the file game.cpp, which contains the implementations of everything declared in game.h and used in whoever includes that header.

So,

sfml-app: main.o game.o
g++ main.o game.o -o sfml-app -lsfml-graphics -lsfml-window -lsfml-system

main.o: main.cpp
g++ -c main.cpp 

game.o: game.cpp game.h
g++ -c game.cpp

this should work

[wispy wren]

you are not paying any attention to OP's issue here

[full nebula]

I don't write make, he's using KDevelop which primarily supports CMake and SFML advises using CMake

also he used a makefile he found on the internet, so there's no guarantee it will work. clearly it did not

[rustic oasis]

!howto ask

[green rivet]

How to Ask a Programming Question

Anyone can ask a question in our programming channels. Following the guide Writing The Perfect Question is recommended.

What to Post

State your problem clearly and provide all necessary details:

• the relevant portion of your code, or all of it
• the expected output
• the actual output (or the full error)
  :trophy: Gold Standard: Minimal Reproducible Example

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* Use /code if you don't know how to format code blocks

[wispy wren]

so did it work?

[wild sequoia]

I did post this thread because the help channel was overcrowded

[wild sequoia]

I'm gonna test this tomorrow or the next day after that

[wispy wren]

do you understand what exactly these lines in the makefile do?

[wild sequoia]

No

Maybe execute terminal commanda

[wispy wren]

yes, and those commands are

#compile game.o from game.cpp only when game.cpp or game.h have been changed
game.o: game.cpp game.h
g++ -c game.cpp

#compile main.o only when main.cpp changed
main.o: main.cpp
g++ -c main.cpp 

#link all the .o object files into the executable
sfml-app: main.o game.o
g++ main.o game.o -o sfml-app -lsfml-graphics -lsfml-window -lsfml-system

[wild sequoia]

@wispy wren makefile:3: *** missing separator. Stop.

[wispy wren]

erase my comments beginning with a hash

[wild sequoia]

same thing but now the second line

[wispy wren]

[wild sequoia]

its the same as before

[wispy wren]

what order did you put the commands into?

[wild sequoia]

just build on the kdevelop

[wispy wren]

what are you talking about

[wispy wren]

sfml-app: main.o game.o
  g++ main.o game.o -o sfml-app -lsfml-graphics -lsfml-window -lsfml-system

main.o: main.cpp
  g++ -c main.cpp 

game.o: game.cpp game.h
  g++ -c game.cpp

each command in the recipe needs to begin with one TAB character

try it

[hearty badger]

I have a basic tutorial on makefiles if you need that: https://github.com/HolyBlackCat/cpp-tutorials/blob/master/articles/multifile_programs.md

[wild sequoia]

Forgot to say that it works

Btw how do I add files

[hearty badger]

Wdym add files??

You mean send to discord?

[wispy wren]

or open your file explorer and drag and drop with the mouse

[wild sequoia]

I meant add files to the makefile

[wispy wren]

well, there's some hacks with *.c

but for now just add a new line at the bottom

[robust viper]

it would be much easier to use the cmake template https://github.com/SFML/cmake-sfml-project

it's very portable, you can use it with any OS/Compiler/IDE/etc

[wispy wren]

if OP doesn't know the syntax of gcc itself, what is the point of this?

[robust viper]

the point is that they don't need to learn it, instead they can use this industry-wide tool that integrate seamlessly into many different code environment.

A working template is provided which means they don't have to toy around with any setting or config

[wispy wren]

don;t need to learn the gcc syntax? what???

[robust viper]

yep!

[wispy wren]

uninstall please

[robust viper]

it's also the official recommended way to setup SFML by the team

[robust viper]

I'm sorry, what's the issue?

[robust viper]

CMake is a meta-build system, you write your config once and then it generates the build config files for whatever buildsystem/IDE/OS/compiler you are using

[hearty badger]

I literally linked a tutorial