If you don’t want to use precompiled headers, then there is no point to using a standard include file – this will slow down the build for every file that includes it and cause them to include extra stuff that they do not need. Get rid of it and just include the headers they need.
What are precompiled headers? Often C++ source files include headers from external libraries. In Windows you include windows.h. These header files can be very large and they take some time to process. Each time you compile a C++ file the compiler has to read and process thousands of lines from these header files. But external … Read more
stdafx.h is a file, generated by Microsoft Visual Studio IDE wizards, that describes both standard system and project specific include files that are used frequently but hardly ever change. Compatible compilers (for example, Visual C++ 6.0 and newer) will pre-compile this file to reduce overall compile times. Visual C++ will not compile anything before the … Read more
The quick answer: the STL and Boost headers do indeed belong in the precompiled header file, even though these header files define template classes. When generating a precompiled header file, a compiler parses the header text (a significant task!), and converts it into a binary format that is optimised for the compiler’s benefit. Even though … Read more
In Xcode, go to your target’s build settings (Command-Option-E, build tab) and uncheck Precompile Prefix Header (GCC_PRECOMPILE_PREFIX_HEADER). You can also remove the value of the Prefix Header setting if you wish. Prefix headers are compiled and stored in a cache, and then automatically included in every file during compilation. This can speed up compilation, and … Read more
Yes it is possible and I can assure you, the time savings are significant. When you compile your PCH, you have to copy the .pdb and .idb files from the project that is creating the PCH file. In my case, I have a simple two file project that is creating a PCH file. The header … Read more
In the Solution Explorer window right click on the *.c file(s) and select Properties. Go to C / C++ -> Precompiled Headers and set the Precompiled Header option to Not Using Precompiled Headers. Also, unless you actually need precompiled headers, I’d say turn it off project-wide. Another option would be to compile your C files … Read more
In C/C++, the #include mechanism is a textual copy of the file specified into the current file. Headers include other headers (which include yet other headers), so when you do a #include, it could be adding tens of thousands of lines of C++ into each cpp file (or cxx, c, whatever), all of which need … Read more
Goto SolutionExplorer (should be already visible, if not use menu: View->SolutionExplorer). Find your .cxx file in the solution tree, right click on it and choose “Properties” from the popup menu. You will get window with your file’s properties. Using tree on the left side go to the “C++/Precompiled Headers” section. On the right side of … Read more
I have definitely had success. First, I used the following code: #include <boost/xpressive/xpressive.hpp> #include <iostream> using namespace std; using namespace boost::xpressive; // A simple regular expression test int main() { std::string hello(“Hello, World!”); sregex rex = sregex::compile( “(\\w+) (\\w+)!” ); smatch what; if( regex_match( hello, what, rex ) ) { std::cout << what[0] << ‘\n’; … Read more