问题
Okay, here's the thing. I have all the IL files I need, namely
DevIL.dll
DevIL.lib
ILU.dll
ILU.lib
ILUT.dll
ILUT.lib
config.h
config.h.in
devil_cpp_wrapper.h
devil_internal_exports.h
il.h
ilu.h
ilu_region.h
ilut.h
ilut_config.h
My project directory looks like this, let's say my project's name is "Project1"
|-Debug---Project1.pdb
|
| |---Debug---[loads of files]
| |
| |---Glut---[OpenGL files]
| |
| |---IL---[all the files mentioned above]
|-Project1---|
| |---image.bmp
Project Folder---| |
| |---[header and .cpp files I made in the project]
| |
| |---[files produced by Visual Studio]
|
|-ipch---[unrelated stuff]
|
|-Project1.sln
|
|-[other files VS created]
I've put all the DevIL files in the IL folder, as mentioned, and I am sure I am using the unicode compatible versions of them, as I am using Unicode Character Set for the project. In my "Additional Dependencies" I have
ilut.lib; ilu.lib; DevIL.lib;
So, the dependencies are there, I know that's not the problem.
After all that, I am still getting linker errors, mainly LNK2019:unresolved external symbol__imp_ for all the IL functions.
What am I missing? It looks to me like maybe something to do with the project properties or the files themselves...maybe I missed a file?
EDIT: Here is the output messages
1>------ Build started: Project: Final Year Project, Configuration: Debug Win32 ------
1>Build started 29/4/2011 12:46:04 pm.
1>InitializeBuildStatus:
1> Touching "Debug\Final Year Project.unsuccessfulbuild".
1>ClCompile:
1> Main.cpp
1>c:\users\xxxx\desktop\final year project 0.2\final year project\main.cpp(152): warning C4390: ';' : empty controlled statement found; is this the intent?
1>c:\users\xxxx\desktop\final year project 0.2\final year project\main.cpp(141): warning C4101: 'alpha' : unreferenced local variable
1>ManifestResourceCompile:
1> All outputs are up-to-date.
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilInit@0 referenced in function "public: static void __cdecl Main::Init(int,char * *)" (?Init@Main@@SAXHPAPAD@Z)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilDeleteImages@8 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilGetData@0 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilConvertImage@8 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilGetInteger@4 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilLoadImage@4 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilBindImage@4 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>Main.obj : error LNK2019: unresolved external symbol __imp__ilGenImages@8 referenced in function "public: static void __cdecl Main::DisplayScene(void)" (?DisplayScene@Main@@SAXXZ)
1>C:\Users\xxxx\Desktop\Final Year Project 0.2\Debug\Final Year Project.exe : fatal error LNK1120: 8 unresolved externals
1>
1>Build FAILED.
1>
1>Time Elapsed 00:00:01.93
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
回答1:
Since you added the build output, the answer is now easy: your linker errors have nothing to do with DevIL at all.
You need to link to SDL (Simple DirectMedia Layer).
Since SDL has a C interface, and - IIRC - doesn't require that the DLL uses the same heap as the application, the VC8 version of the "Development Libraries" should do fine (even if you use VC10). Just add SDL.lib to the "Additional Dependencies" and you should be fine.
EDIT
OK. You're either
- not linking against the required .lib files (DevIL.lib etc.) or
- linking against corrupted/wrong .lib files
At least there is no other explanation I can think of.
The names mentioned in your build log (__imp__ilInit@0 etc.) are correct, and the current "DevIL SDK" (DevIL 1.7.8 SDK for 32-bit Windows) works fine with VC10 (I just verified it).
To assure you're linking against DevIL.lib etc. please put the following in your main.cpp file:
#pragma comment(lib, "DevIL.lib")
#pragma comment(lib, "ILU.lib")
#pragma comment(lib, "ILUT.lib")
To make sure you're linking against the correct version of those files, re-download the whole SDK and try again with the new files.
EDIT 2
Since I got half the reward, I feel I should be more helpful :)
One last thing you can try: enable verbose linker output to check if the linker finds the correct version of DevIL.lib. (If it didn't find any DevIL.lib, you would get an error LNK1104: cannot open file 'DevIL.lib' - and since you're not getting that message, that cannot be the problem.)
To enable verbose linker output, add the /VERBOSE switch (under Configuration Settings -> Linker -> Command Line -> Additional Options).
That will give you a ton of messages. Copy them into your favorite editor, and search for lines containing DevIL.lib. One of the lines should read Searching X:\path\to\DevIL.lib: - that's the path to the copy of DevIL.lib the linker is using. If that's not the path where you copied the files from the SDK you downloaded, you have found the problem.
And if there are no lines containing DevIL.lib, then the linker isn't even trying to locate it. However I've never seen #pragma comment fail, so if you indeed added those lines that almost surely cannot be the case.
BTW: please let me know if you managed to solve this. This is so strange that I really want to know what was going on :)
回答2:
You need to tell the linker to link against the IL libs.
Project settings, Linker, Input
Make sure the directory the libs are in is in the Additional directorys field too.
回答3:
I've noticed your config.h.in file should have .win extension because that it is in DevIL-SDK-x86-1.7.8.zip package. And there's no devil_cpp_wrapper.h file also.
Finally i solved this in this way:
- Header files
- config.h
- config.h.win
- devil_internal_exports.h
- il.h
- il_wrap.h
- ilu.h
- ilu_region.h
- ilut.h
- ilut_config.h
goes to VC include directory - all in one directory named IL (c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include\IL\ by default)
- Liblary files
- DevIL.lib
- ILU.lib
- ILUT.lib
goes to lib directory (c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\lib\ by default)
- DLL files
- DevIL.dll
- ILU.dll
- ILUT.dll
goes to project dorectory (...\Project Folder\Project1\ in your case)
Then i added liblary files to project by right click on project->Properties->Linker->Input->Additional Dependencies (wrote just name of liblaries like ILU.lib)
In my project I just include IL\il.h, IL\ilu.h and IL\ilut.h
I think you may got wrong files by the way...
回答4:
Just in case you never got this worked out, or anyone else has the same problem (like I did): I had downloaded the 64-bit version of DevIL for my 64-bit Windows computer, but Microsoft Visual Studio (I was using Express) was the 32-bit version. I downloaded the 32-bit version of DevIL and it worked!
回答5:
I had the same problem. Seems like the pre-built binaries are swapped: I could link to the ones designated as non-unicode but they would utterly fail trying to use my non-unicode strings and return unicode strings. Try to build your own binaries from the source or use a previous version.
回答6:
you should compare the function signatures that you see in your errors with the signatures you get with depends.exe (depedency walker). If they differ there may be a compiler-issue. You may then try to compile with :
extern "C" {
// put your devils-include directives here ...
}
Nothing garantied of course , just a suggestion.
You may also check the 'Additional Library Directories' property on your 'Linker\General' page to see if (when used) it points to the right directory for your build (if you also added a path to the standard VC lib-directories their may be a conflict ,use either one but not both).
Another suggestion is to create a new project and do it all over again ,you may have made an ever so little mistake.
Good luck !
回答7:
I had the same problem. In my case it was problem with code in all devil`s .h files
#ifdef _WIN32
#if (defined(IL_USE_PRAGMA_LIBS)) && (!defined(_IL_BUILD_LIBRARY))
#if defined(_MSC_VER) || defined(__BORLANDC__)
#pragma comment(lib, "%LIBNAME%.lib")
#endif
#endif
#endif
after second #if code was deactivated.
i added #pragma comment(lib, "DevIL.lib") (and 2 more) into my main.h and linker errors dissapeared.
sorry for my bad english =[
回答8:
I don't know if this question is still active, but since it has no chosen answer, I'll post this. I had what seems like the exact same problem with DevIL version 1.7.8. To fix it, I rolled back the version to 1.7.7 and used #undef _UNICODE before including the headers and #define _UNICODE afterwards. The project compiled without linker errors and worked without a hitch. On 1.7.8, the libraries seem to all be unicode, or at least they don't seem to support ascii very well. However, this may just be some weird compatibility issue with my computer as it does not seem to be a common problem
回答9:
It might be that you have to declare some preprocessor variable to actually tell the compiler that you are importing symbol; I mean something related to __declspec( dllimport )
回答10:
I did exactly as what Sarah said about the 32-bit or 64-bit Visual Studio versions. I'm on a 64-bit computer running a 32-bit Visual Studio 2012. I obtained this error when I used the x64 DevIL files. Getting the x86 version helped. Here's the basic steps I took to ensure it does run:
Right-click your project and go to Properties.
Under C/C++ > General, add DevIL's 'include' folder under Additional Include Directories.
Then under Linker > General, add DevIL's 'lib' folder (it should contain: DevIL.lib, ILU.lib and ILUT.lib) to Additional Library Directories. For x64 it may not contain a lib folder, it may be just the DevIL directory itself (for version 1.7.8 it was that case).
Also in Linker > Input, add those .lib file names into Additional Dependencies.
Now that should be all you need to do in the project properties. In the main.cpp you should include the appropriate header files and it should work when you initialize.
Example:
#include "IL/il.h"
#include "IL/ilu.h"
#include "IL/ilut.h"
int main(){
ilInit();
iluInit();
ilutRenderer(ILUT_OPENGL); //these are just to initialize
}
来源：https://stackoverflow.com/questions/5743235/devil-library-files-and-dependencies