unresolved externals with glew when other glew functions work

Question

I'm following this tutorial for openGL along with SDL. I'm mildly familiar with SDL and have slightly dipped my toes in openGL. So I'm reading that tutorial and things are going great until I try to actually compile the code... I'm using Cmake to compile the code. It's also important to note that I've just stuck all of the glew headers and libs in with all of the SDL2 libs and headers.

Here's my cmakelists file-

    cmake_minimum_required(VERSION 3.7)

    project(opengl)

    find_package(SDL2 REQUIRED)

    include_directories(${SDL2_INCLUDE_DIRS})

    add_executable(opengl src/main.cpp)
    target_link_libraries(opengl ${SDL2_LIBRARIES})

Here's my SDL2-Config.cmake file-

    set(SDL2_INCLUDE_DIRS "${CMAKE_CURRENT_LIST_DIR}/include")

    # Support both 32 and 64 bit builds
    if (${CMAKE_SIZEOF_VOID_P} MATCHES 8)
      set(SDL2_LIBRARIES "${CMAKE_CURRENT_LIST_DIR}/lib/x64/SDL2.lib;${CMAKE_CURRENT_LIST_DIR}/lib/x64/SDL2main.lib;${CMAKE_CURRENT_LIST_DIR}/lib/x64/glew32.lib;" )
    else ()
      set(SDL2_LIBRARIES "${CMAKE_CURRENT_LIST_DIR}/lib/x86/SDL2.lib;${CMAKE_CURRENT_LIST_DIR}/lib/x86/SDL2main.lib;${CMAKE_CURRENT_LIST_DIR}/lib/x86/glew32.lib;")
    endif ()

    string(STRIP "${SDL2_LIBRARIES}" SDL2_LIBRARIES)

and here's my main.cpp file-

    #include <GL/glew.h>
    #include <iostream>
    #include <SDL.h>
    #include "SDL_opengl.h"
    #define GL3_PROTOTYPES 1

    #undef main

    int main()
    {

        SDL_Init(SDL_INIT_VIDEO);

        SDL_Window* window = SDL_CreateWindow("My Game", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 512, 512, SDL_WINDOW_OPENGL);
        SDL_GLContext context = SDL_GL_CreateContext(window);

        glewInit();

        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
        SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

        SDL_GL_SetSwapInterval(1);

        glewExperimental = GL_TRUE;

        while(true){
            //set color
            glClearColor( 1.0, 0.0, 0.5, 1.0 );

            // clear back buffer
            glClear( GL_COLOR_BUFFER_BIT );

            // swap back and front buffer
            SDL_GL_SwapWindow(window);
        }
        return 0;
    }

Now this all looks good to me, but I'm no expert.

The confusing part is that the glew functions such as glewInit(), among others, work fine! But when it comes to compile the code I am smacked in the face with two unresolved externals. heres the error code-

    PS C:\C++Dev\SDLDEV\openGL\build> cmake --build .
    Microsoft (R) Build Engine version 16.4.0+e901037fe for .NET Framework
    Copyright (C) Microsoft Corporation. All rights reserved.

      main.cpp
    main.obj : error LNK2019: unresolved external symbol __imp_glClear referenced in function main [C:\C++Dev\SDLDEV\openGL
    \build\opengl.vcxproj]
    main.obj : error LNK2019: unresolved external symbol __imp_glClearColor referenced in function main [C:\C++Dev\SDLDEV\o
    penGL\build\opengl.vcxproj]
    C:\C++Dev\SDLDEV\openGL\build\Debug\opengl.exe : fatal error LNK1120: 2 unresolved externals [C:\C++Dev\SDLDEV\openGL\b
    uild\opengl.vcxproj]

any help is very much appreciated!

you are not linking against the opengl32 library. SDL alone is not enough. — BDL, Mar 30 '20 at 21:11
You need to link against `glew32.lib`. See the "Setting it up" section in the tutorial you linked. — Louen, Mar 30 '20 at 21:11
Does this answer your question? [What is an undefined reference/unresolved external symbol error and how do I fix it?](https://stackoverflow.com/questions/12573816/what-is-an-undefined-reference-unresolved-external-symbol-error-and-how-do-i-fix) — BDL, Mar 30 '20 at 21:13
where do i get the opengl32 lib, i assumed that was the problem, but didnt find it anywhere — Jcsq6, Mar 30 '20 at 21:15

unresolved externals with glew when other glew functions work

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