How to statically link the C++ REST SDK (Casablanca)

You are trying to use the C++ REST SDK (Casablanca) in your Windows application. You have one of the following problems:

• you need Windows XP support
• when your code executes you receive a debug assertion: _pFirstBlock == pHead
• you get unpredictable behaviour or random crashing
• you need to build an application which links against static libraries

You have 30 minutes to solve the problem. Here is how:

The issue is that the C++ REST SDK only supports dynamic linking. The solution is to re-build the SDK with static linking.

Install Git for Windows

Git is a source code repository management tool which you’ll need to access the C++ REST SDK source tree.

Download Git SCM.

Run the installer. Leave all the options at their defaults except on the page where you select what to add to the PATH environment variable. Choose to add the Git executable to your path.

Obtain the source code

Open a command prompt (press Start+R, type cmd and press Enter).

Use cd to navigate to the directory where you want to place the code and mkdir to create a directory to store the code, eg:

cd C:\Users\MyUserName\Documents\Visual Studio 2013\Projects
mkdir cpprest


Use git to obtain the source tree:

git clone https://git01.codeplex.com/casablanca cpprest


Replace cpprest with the target directory to store the code.

Open solution in Visual Studio

There are four .sln files. Select the correct one as follows:

• casablanca110.desktop.sln – Windows XP / Vista / 7, Visual Studio 2012
• casablanca110.WinRT.sln – Windows 8 / Metro, Visual Studio 2012
• casablanca120.desktop.sln – Windows XP / Vista / 7, Visual Studio 2013
• casablanca120.WinRT.sln – Windows 8 / Metro, Visual Studio 2013

In the Source folder, you will see projects named casablanca1x0 and casablanca1x0.xp. The former is for Windows Vista and Windows 7, the latter is for Windows XP. Right-click on the project you wish to build and choose Properties.

Change from dynamic to static linking

Select All Configurations and All Platforms from the drop-downs at the top of the Properties dialog.

In Configuration Properties -> General -> Project Defaults, change the Configuration Type option to Static library (.lib).

In Configuration Properties -> C/C++ -> Code Generation, change the Runtime Library option to Multi-threaded Debug (/MTd) for the Debug configuration and Multi-threaded (/MT) for the Release configuration.

In Configuration Properties -> C/C++ -> Preprocessor for All Configurations, add the text _NO_ASYNCRTIMP; to the Preprocessor Definitions option. This prevents the compiler from trying to export the functions to a DLL.

Click OK to save the changes.

Build the project

Right-click the project and choose Build. Make sure you do this for each configuration and platform you want to build for.

In the folder you created for the source tree, open Binaries\Win32\Debug and rename cpprest120d_2_0.lib to cpprest120_2_0.lib (remove the ‘d’). Note that the library name will include 110 rather than 120 for Visual Studio 2012 builds and the two final digits representing the SDK version may be different. This article is based on version 2.0.

Prepare your application

Open the solution for the application you want to build, right-click on it and choose Properties.

Select All Configurations and All Platforms from the drop-downs at the top of the Properties dialog.

In Configuration Properties -> VC++ Directories, add a new entry in Include Directories as follows:

C:\PathToCppRESTSDK\Release\include

In Configuration Properties -> VC++ Directories, add a new entry in Library Directories as follows:

C:\PathToCppRESTSDK\Binaries\Win32\$(Configuration)

In Configuration Properties -> C/C++ -> Preprocessor, add the text _NO_ASYNCRTIMP; to the Preprocessor Definitions option. This prevents the compiler from trying to find the C++ REST SDK functions from a DLL.

In Configuration Properties -> Linker -> Input, add winhttp.lib and cpprest120_2_0.lib (replacing the numbers with the correct Visual Studio and C++ REST SDK version numbers) to the Additional Dependencies option.

Build your project.

If all goes well, you should now have a statically linked version of the SDK which is linked in your application with no linker errors.

I hope you found this guide useful!

References

C++ REST SDK – Statically Linked Runtime

C++ REST SDK – How to setup, build and run tests on Windows

Git for Windows