How to force WinAPI version... WINVER or _WIN32_WINNT?

[jdx-john]

I wonder if some runtime errors we are having are down to mismatch in build between our code and vcpkg ports.

The docs (https://vcpkg.readthedocs.io/en/latest/users/triplets/) say we can use:

VCPKG_CXX_FLAGS
Sets additional compiler flags to be used when not using VCPKG_CHAINLOAD_TOOLCHAIN_FILE.

e.g.: set(VCPKG_CXX_FLAGS -D_WIN32_WINNT=0x600)

But a few quick questions:

1. Should I be using WINVER or _WIN32_WINNT? (I know this is a WinAPI question not vcpkg but I never knew the distinction)
2. How can I check my changes have 'stuck' / been applied in a build, to know my output has the specified changes (or not)?

[autoantwort]

1. According to this you should set NTDDI_VERSION and _WIN32_WINNT
2. When you run vcpkg install --triplet=... and it says everything is up to date, then it your changes should be respected. But Afaik _WIN32_WINNT does not change runtime behavior. It only enables more functions in the windows headers.

[autoantwort]

In manifest mode that should work.

[jdx-john]

We cannot use MF unfortunately, or at least we haven't found a way to so far. Seems like that's all MS focus on now unfortunately.

[autoantwort]

What is your problem with MF? Multiple triplets at the same time are supported. I don't know a feature that is supported by classic mode but not by MF mode.

[jdx-john]

When I last looked multiple triplets were not supported... things change so fast! The specific case we have is a solution of ~100 projects using multiple build configurations (32/64 bit for example). When I looked into MF a few months back I just couldn't get that to work nicely.

[autoantwort]

Yeah we had the same problem at work. But #19767 changed where things get installed so you can now use MF mode with a solution and 32/64 projects.