C++ - How to make a program compiled with MinGW standalone?

Question

I am working on a project(for Windows) that is small and should be portable. I saw somewhere that MinGW gets rid of the requirement of some .dlls on the target system, so I thought I'd give it a try. To my suprise, when I tried running my program on a friend's computer, I got two errors saying that 2 different .dlls were missing. I thought MinGW used the system dlls, but it obviously didn't work. I saw an article on how to make a standalone exe with Visual Studio, but I'd prefer to use MinGW due to it's simplicity.

So my question: How to produce a standalone exe with MinGW?

Note: I am only using standard libraries, but it'd be nice to know how to include other libraries for future projects.

If you'd like an example of what I mean by a standalone exe, putty is a good example(it is an ssh client for Windows).

Answer 1

The two libraries you needed were most likely libgcc_s_sjlj-1.dll and libstdc++-6.dll or some variation of these, depending on how your mingw was configured when it was built. These are C and C++ standard library implementations.

If you want, you can pass extra flags to the compiler when you are linking the final executable, -static-libgcc and -static-libstdc++ , which will cause it to link these libraries in statically instead of requiring you to distribute DLLs for them with your executable.

More info here: Mingw libgcc_s_sjlj-1.dll is missing

In general you can always try to statically link libraries into your executable. These special -static-libgcc flags are special flags provided only by mingw, not by other compilers, and not for other libraries, you use a different -static syntax for other libs. Static linking is fine but it gets more complicated and error prone as the dependencies get more complex. Static linking has some pitfalls associated to the order in which the libraries are linked. After a certain point, its usually simpler to make them all shared and don't do any static linking. It's up to you, it depends on how complex your project gets / if you start to have problems.