![]() If different source files in your project use different sets of header files, consider moving the most common headers into the pch.h file. In this example, it translates to 3.5 seconds + linking time instead of 7.5 seconds + linking time: Modifying the contents of the main source file (but not the headers included from pch.h) will not require rebuilding the precompiled header file. Precompiling the headers also speed up partial rebuilds.The updated timing shows how precompiling the header file added extra 7.2 seconds at the beginning of the build, however the subsequent compilations of the regular source files were sped up more than 2x: The overall speedup will be greater for projects with more source files.Add “ echo %time” between the compiler invocations: Note how it now contains a line for precompiling pch.h. Build the project and open the updated batch file.Similarly to the regular Win32 projects, the pch.cpp file is needed because MSBuild does not build the header files directly. gch file, and will then load when building the regular source files, instead of actually parsing pch.h over and over. Add another source file called pch.cpp, include pch.h from it and set “ Precompiled Header” to “ Create” just for that file: This ensures that VisualGDB will first precompile pch.h file into a.Also set the precompiled file name to pch.h: Go to VS Project Properties -> C/C++ -> Precompiled Headers and set the Precompiled Header option to “ Use“.Update both source files to include the pch.h file that, in turn, includes the actual headers:.Create a new file called pch.h and copy the #include directives from either of the source files into it: Precompiled headers speed up the building of large projects by first precompiling a set of commonly used header files, and then simply loading it for each compiled file.If the project was larger, every source file using these header files would take at least 5 seconds to build. Run the batch file and note the times it took for both sources to build: In this example, the original TCP server example took 7 seconds to build, while an empty source file with just the #include directives took another 5 seconds.Add “ echo %time%” between the GCC invocations to measure the exact time it takes to run gcc: VisualGDB will generate a batch file with all the build commands. ![]() Open VS Project Properties -> Configuration Properties -> Local Build and set Generate a. Now we will measure the exact time it takes to build the project.Copy the #include directives from the main source file to the newly added file and do not add any code after them:.To simulate a larger project with multiple source files using the same headers, add another source file via Solution Explorer: Try building the project and ensure it succeeds.Instead, the full library name including the “ lib” prefix and the version should be used, prefixed by a colon: Note that Boost uses versioned library names, so just adding “ boost_system” to Additional Library Names would not work. Then add “ pthread” and “ :libboost_system.so.” to the Additional Library Names in VS Project Properties. Replace the contents of the main source file with the boost asynchronous TCP server example.Boost gets installed into the regular library locations, so the default sysroot synchronization options will work:.If you are using a cross-compiler, you would need to synchronize the sysroot directory to make sure the cross-toolchain can find the boost headers and libraries:.Then run “ sudo apt-get install libboost-dev” or “ sudo yum install libboost-dev” depending on the package manager you are using:.In order to install Boost on the target, open the SSH console for it: Once a basic project is created, we will update it to use the Boost library that will considerably slow down the build due to very heavy C++ header files. Both options support precompiled headers: Select the Linux machine you would like to target and choose whether you want to build the project directly, or use a cross-compiler. ![]() ![]() ![]() Precompiled headers are supported out-of-the-box for MSBuild projects and can be manually enabled for CMake-based projects:
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