Does ld link dynamically to the runtime libraries by default?

[TheShermanTanker]

Does the ucrt64 toolchain link dynamically to ucrtbase.dll and libstdc++.dll by default? Asking because the final binaries generated by the compiler are at the very least a whopping 133KB in size even for tiny programs, which leads me to believe that the libraries might be getting statically linked quietly (or if other Windows libraries such as user32 are getting pulled into the binary without me knowing), but I can't be sure since I don't have a way to check whether they are

[Biswa96]

Does the ucrt64 toolchain by default link dynamically to ucrtbase.dll and libstdc++.dll by default?

Yes.

the final binaries generated by the compiler are at the very least a whopping 133KB in size even for tiny programs

strip can make it smaller.

[Biswa96]

I am not deeply familiar with those options. But with my quick poking, it looks like --gc-sections works but -ffunction-sections or -fdata-sections does not. Other experts can provide some details. You can investigate with mapfile and --print-gc-sections options.

[TheShermanTanker]

Yes.

Strangely when I try running the compiled binaries with libstdc++.dll in a directory where it can't be found they all work just fine, shouldn't they not be working if they really were dynamically linked to it?

[Biswa96]

You can use ntldd tool to find if the executable is really linked with stdc++. Install the ntldd package in mingw. Or there is a GUI tool also, called Dependencies.

[mati865]

Function sections are basically broken with GCC when targeting Windows.
They work fine in Clang. However just like on Linux to use them the libraries have to be built with them.

[mati865]

Strangely when I try running the compiled binaries with libstdc++.dll in a directory where it can't be found they all work just fine, shouldn't they not be working if they really were dynamically linked to it?

Maybe there is libstdc++.dll in your PATH?
Just like Biswa96 said ntldd is the great tool to find dependencies.

[revelator]

aye i usually add -fno-function-sections -fno-data-sections when building gcc as these seem to be elf related.