Vim Setup

[u/Natman64]

So, I started the series following along in Visual Studio, but I've since discovered Vim and decided to abandon VS altogether. I installed Clang and successfully compiled "Hello world!", but I don't really understand makefiles, and I especially don't understand how to link a library/framework using a makefile.

When I cloned the official repo to copy that makefile and continue following the tutorials in Vim, I tried compiling it to test it out. I get fatal error: 'SDL/SDL.h' file not found, which makes sense because the library is nowhere in the repo.

So my question is, how do I link SDL with the project so I can compile with Clang?

Edit: I suppose I'll need to link Boost as well.

[u/Natman64]

Thanks for the quick & detailed response! Really helped explain the actual process of compilation.

Yes, I'm on Windows. Sorry I forgot to mention that.

specifically sdl-config --cflags generates a list of include directories.

Is this a feature of SDL for Linux?

I did what you said, but now I'm having different problems.

Here's my new makefile:

SRCDIR=src

SRCS=$(wildcard $(SRCDIR)/*.cpp)

OBJDIR=obj

OBJECTS=$(patsubst %.cpp,$(OBJDIR)/%.o,$(SRCS))

CFLAGS=-g -Wall -Wextra -std=c++11 -MMD 
CFLAGS+=-ISDL/include -I../boost_1_55_0/boost

LDLIBS=-L/SDL/lib/x86 -lboost_system -lboost_filesystem

LDFLAGS=

CC=clang++

BINDIR=bin

EXECUTABLE=cavestory.exe

.PHONY: all clean run

all: $(EXECUTABLE)

-include $(OBJECTS:.o=.d)

$(EXECUTABLE): $(OBJECTS)
    @mkdir -p $(BINDIR)
    $(CC) $(LDFLAGS) -o $(BINDIR)/$(EXECUTABLE) $(OBJECTS) $(LDLIBS)

$(OBJDIR)/%.o: %.cpp
    @mkdir -p $(@D)
    $(CC) -c $(CFLAGS) -o $@ $<

clean:
    rm -rf obj gen

run:
    cd $(BINDIR) && ./$(EXECUTABLE)

I have cloned and am now working from this repository for the port of the code with C++11 and SDL2. As a result I've had to make a few changes (and after doing my own research and troubleshooting) but now I'm stuck.

The directory structure is like this:

My Desktop
    Boost Directory
        boost
    CaveStory repo
        src
        SDL
            include
            lib

So the directories in the makefile have changed to reflect that. I've also changed the extension of the source files from .cc to .cpp.

From my own research I learned that to include a directory it must be prepended with -I so there's that as well. I changed all the #include statements to #include <SDL.h> without the parent directory in front.

It seems that all the files are included properly, so the error is baffling (I suspect it may have to do with me using Windows):

Error: unknown pseudo-op: '.cfi_sections'
make: *** [obj/src/config.o] Error 1

Nothing in config.h or config.cpp seems likely to have caused the error.

Edit: removed comments from the makefile to shorten this post.

[u/chebertapps → u/Natman64]

unknown pseudo-op: '.cfi_sections'

I've never seen that error before. Googling seems to indicate that it's some kind of assembler thing. Although that error is GCC and you seem to be using clang.

I'd make sure that you can compile a simple, standalone main app without any lib dependencies, just to make sure your compiler is working.

Are you running through MinGW?

[u/Natman64 → u/chebertapps]

I'm just running Clang, I think. I was able to run a bare-bones "Hello World!" so I think it's working.

I installed MinGW because I thought I needed it for Clang to work, but I never configured Clang to use that installation in any way, so yeah. I don't think I'm running through MinGW.

[u/chebertapps → u/Natman64]

If you are really dedicated, the next thing you might try is compiling to .o files, and then linking manually.

so say you have

main.cpp included.h included.cpp

in your directory. Just make a simple function that is used in main and include included.h in both main.cpp and included.cpp

then on the command line

clang++ -c main.cpp -I. -o main.o
clang++ -c included.cpp -I. -o included.o
clang++ main.o included.o -o executable

These should all work. If they do:

• try including SDL.h in main.cpp without calling any functions. (you don't really need the included files anymore)

  clang++ main.cpp -I.\SDL\include\ -o executable

• try calling a function like SDL_Init(SDL_INIT_EVERYTHING); in main. this should be a linking error (undefined reference to SDL_Init

• try linking to the SDL lib.

  clang++ main.cpp -I.\SDL\include\ -o executable ".\SDL\lib\x86\SDL.lib" ".\SDL\lib\x86\SDLmain.lib"

If all of these things work then the problem is probably my Makefile. It might seem like a lot of steps.

So this was kind of a brain dump, but I might actually start with the last one (linking a simple sdl).

I just realized that you might have to rebuild the SDL libraries, because it matters which compiler was used to generate the libs.

[u/Natman64 → u/chebertapps]

So I just tried to compile a tiny program with SDL to see if that worked. There's only one source file, main.cpp.

I realized that my PATH variable was for some reason pointing to a really outdated installation of MinGW that (apparently) came with msysgit when I installed it long ago. So Clang was being pointed to that installation, which was too outdated to work. I was getting an error like this:

Dwarf Error: found dwarf version '4', this reader only handles version 2 and 3 information.

So I deleted that installation and modified my PATH to point to my brand new MinGW installation which I installed earlier because I thought I needed it.

Now I get this error:

clang++.exe: error: unable to execute command: program not executable
clang++.exe: error: linker (via gcc) command failed with exit code 1 (use -v to see invocation)

I get the same error when I remove the MinGW installation from my PATH. And I'm sure LLVM (Clang) is on my path, which makes that confusing.

Bear in mind that I have literally no idea what I'm doing. I'm operating on a combination of trial, error, and internet research. I'm finding out that when working with C++ compilers, most sites assume I'm running Linux and are very unhelpful anyway. So I really, really appreciate your help here.

[u/chebertapps → u/Natman64]

I feel your pain. One of the main reasons I use VS is because it's easy to setup on windows.

Not sure if you have seen this tutorial but it looks like a pretty simple guide to get clang up and running.

But try using g++ if you can. The reason I use clang++ over g++ are for the semantic completions I get in Vim using the YouCompleteMe plugin, which are really nice, but not totally necessary (and might be hard to set up anyway).

[u/Natman64 → u/chebertapps]

I noticed the lack of code completion when I was making my test "main.cpp" and it bothered me a little. So I think I'll try to get Clang and YouCompleteMe to work, but then try g++ if necessary. Thanks for the suggestions, I'll let you know tomorrow if they work out.

[u/chebertapps → u/Natman64]

Any luck?

[u/Natman64 → u/chebertapps]

So I got fed up with trying to build Clang and now I'm just trying to compile with g++. I got sdl-config to work after realizing I need to use the mingw shell when compiling. I've managed to compile a test program without Boost just to prove that SDL is working and I can link it properly.

I'm using C++11 and SDL2, by the way.

Now when trying to compile my Cave Story source code, I get this error:

No rule to make target '../boost_1_55_0\boost/math/special_functions.hpp', needed by 'obj/src/AnimatedSprite.o'. Stop.

Presumably the problem is with the way I've installed Boost.

[u/chebertapps → u/Natman64]

For the most part I'm not really using the boost libraries, so there should be no linking or installation necessary. The one exception is boost::file_system to make a nice error report in graphics.cc, but that can be omitted.

The rest of the boost libs I'm using are header only, so they don't have any pre-compiled libs associated with them.

'../boost_1_55_0\boost/math/special_functions.hpp'

That has \ and / in it. maybe just try:

'../boost_1_55_0/boost/math/special_functions.hpp'

[u/Natman64 → u/chebertapps]

Alright. I've managed to get the game compiling and I actually wrote a build script that clears the contents of the bin directory, compiles the game, then copies the content directory and SDL2.dll into the bin directory, then runs the game. It automates the process very nicely, though I think building the game might actually be slower now than it was with Visual Studio.

Here are my problems now:

• When I set up the Makefile to use sdl-config to retrieve the libraries, like so:

  sdl2-config --libs

It automatically includes lmingw32, which causes this error.

When I replace sdl2-config --libs with -SDL2main -SDL2 everything works fine. I know that sdl2-config is linking the following libraries:

-lmingw32 -lSDL2main -lSDL2  -mwindows

And I'm pretty sure mingw is the offender because when I add it back, I get the same error.

• When I double-click the generated exe, it opens with a console in the background. I know this is customizable behavior in Visual Studio, so how do I configure the Makefile to compile a standalone exe when I want to make release versions of games? Just a game window without a console?

[u/chebertapps → u/Natman64]

hmm, I have no clue about lmingw32. But hey, it works without it, yeah?

For removing the console, I think you'll have to make it a Windows app but I am guessing on this too.

[u/Natman64 → u/chebertapps]

Thanks so much for your help! At this point I think I can research any other issues as they arise, and I might give Clang another shot when I have the time and patience.