Aws-sdk-cpp: [UE4] Undefined Reference Aws::Http::CONTENT_TYPE_HEADER

Created on 26 Jun 2018 · 4Comments · Source: aws/aws-sdk-cpp

What platform/OS are you using?

Windows 10 Pro 1803 17134.112 64-Bit
AWS C++ SDK 1.4.74

What compiler are you using? what version?

Visual Studio 2017 Community Edition 15.7.3
Unreal Engine 4.19.2

What's your CMake arguments?

cmake ../ -G "NMake Makefiles" -DTARGET_ARCH=WINDOWS -DBUILD_ONLY="core;gamelift" -DCUSTOM_MEMORY_MANAGEMENT=0 -DBUILD_SHARED_LIBS=1

Can you provide a TRACE level log? (sanitize any sensitive information)

Hey,

i have builded the AWS SDK successfully, but if i use the SDK with Unreal Engine 4 in my plugin, to integrate Gamelift, the linker throws the error below.

Error: LNK2001 undefined reference "char const * const Aws::Http::CONTENT_TYPE_HEADER" (?CONTENT_TYPE_HEADER@Http@Aws@@3PEBDEB)". PluginTest D:\PluginTest\Intermediate\ProjectFiles\Module.GameLiftPlugin.cpp.obj

can anyone help me out?

thanks

Source

Tolan87

Most helpful comment

Ok, finally i found a working solution, let me share the solution for other Unreal Developer that run into this problem.

Dynamic linking a library of AWS C++ SDK need the preprocessor directive below.

USE_IMPORT_EXPORT

How you can add it to your Visual Studio Project Solution?

When you use a plugin or a module(a game himself is module) u can add a public definition in the _PluginOrModuleName.Build.cs_ file like the example below.

public class MyPlugin : ModuleRules
{
    public MyPlugin(ReadOnlyTargetRules Target) : base(Target)
    {
        PCHUsage = ModuleRules.PCHUsageMode.UseExplicitOrSharedPCHs;
        bEnableExceptions = true;

        PublicDependencyModuleNames.AddRange(new string[] {
                "Engine",
                "Core", 
                "CoreUObject", 
                "InputCore", 
                "Projects", 
                "AWSCore" 
        });

    PublicIncludePaths.AddRange(new string[]{
            "GameLiftClientSDK/Public"
        });

    PrivateIncludePaths.AddRange(new string[] {
            "GameLiftClientSDK/Private"
        });

        PublicDefinitions.Add("USE_IMPORT_EXPORT");

        .....
    }
}`

If your build fail again, it´s can be needed to delete the _Intermediate_ and _Binaries_ folder and let regenerate your Visual Studio Project files by Unreal.

Regards ;)

Tolan87 on 26 Jun 2018

👍4 ❤3 🎉2

All 4 comments

Ok, finally i found a working solution, let me share the solution for other Unreal Developer that run into this problem.

Dynamic linking a library of AWS C++ SDK need the preprocessor directive below.

USE_IMPORT_EXPORT

How you can add it to your Visual Studio Project Solution?

When you use a plugin or a module(a game himself is module) u can add a public definition in the _PluginOrModuleName.Build.cs_ file like the example below.

public class MyPlugin : ModuleRules
{
    public MyPlugin(ReadOnlyTargetRules Target) : base(Target)
    {
        PCHUsage = ModuleRules.PCHUsageMode.UseExplicitOrSharedPCHs;
        bEnableExceptions = true;

        PublicDependencyModuleNames.AddRange(new string[] {
                "Engine",
                "Core", 
                "CoreUObject", 
                "InputCore", 
                "Projects", 
                "AWSCore" 
        });

    PublicIncludePaths.AddRange(new string[]{
            "GameLiftClientSDK/Public"
        });

    PrivateIncludePaths.AddRange(new string[] {
            "GameLiftClientSDK/Private"
        });

        PublicDefinitions.Add("USE_IMPORT_EXPORT");

        .....
    }
}`

If your build fail again, it´s can be needed to delete the _Intermediate_ and _Binaries_ folder and let regenerate your Visual Studio Project files by Unreal.

Regards ;)

Tolan87 on 26 Jun 2018

👍4 ❤3 🎉2

Make sure to create the cmake output folder inside the sdk source code, didn't work for me outside of it

SyedAman on 27 Jun 2018

Glad that you found a way out. If you generate your project using cmake, you can actually add this macro into you cmake script.

singku on 3 Jul 2018

@singku How to add this macro into my cmake script? I tried add "add_definitions( -D USE_IMPORT_EXPORT )" or "add_compile_definitions(USE_IMPORT_EXPORT)" in CMakeLists.txt file under aws-sdk-cpp, and then run the cmake command. But they doesn't work. Am I using the wrong method?