unresolved external symbol _stbi_load

[andrepcg]

I'm using Visual Studio and the stb_image.h library.

If I call stbi_load in my program I get the following errors:

Error   3   error LNK2019: unresolved external symbol _stbi_load referenced in function "public: bool __thiscall CubemapTexture::Load(void)" (?Load@CubemapTexture@@QAE_NXZ)    ...\CubemapTexture.obj
Error   40  error LNK2001: unresolved external symbol _stbi_load    ...\Texture.obj

[Nairou]

From stb_image.h:

Do this:
#define STB_IMAGE_IMPLEMENTATION
before you include this file in one C or C++ file to create the implementation.

[andrepcg]

I missed that line...

I did that in my Utils.h file. Now I'm trying to access the functions in another file that is including Utils.h but I still get errors:

Error   276 error LNK1169: one or more multiply defined symbols found   ...\3PS.exe
Error   274 error LNK2005: _stbi_zlib_decode_noheader_malloc already defined in 3PS.obj ...\Utils.obj
....

I've checked and the fname.obj are all the files referencing Utils.h

[Nairou]

That's because STB_IMAGE_IMPLEMENTATION needs to be defined within a .c or .cpp file, not within a header. When you define STB_IMAGE_IMPLEMENTATION, you are creating the bulk of the stb_image code. You only want that code to exist once, like the code in your own project, which is why it has to be defined within a .c or .cpp file.

[andrepcg]

Thanks, solved it!