'Unicode support requires compiling with /utf-8' compiling with msvc

[Karma5s]

vcpkg_installed\x64-windows\x64-windows\include\fmt\base.h(458,28): error C2338: static_assert failed: 'Unicode support requires compiling with /utf-8'
when compiling with MSVC following this tutorial
https://learn.microsoft.com/en-us/vcpkg/get_started/get-started-msbuild?pivots=shell-powershell

Originally posted by @Karma5s in #40944 (comment)

[JonLiu1993]

@Karma5s, could you provide detailed steps to reproduce? I can successfully build fmt with MSVC following this tutorial
https://learn.microsoft.com/en-us/vcpkg/get_started/get-started-msbuild?pivots=shell-powershell

[JackBoosY]

Please provide fmt configure logs and build logs.

[RainesArt]

You can try Adding Command Line /utf-8 seems to work.

[github-actions]

This is an automated message. Per our repo policy, stale issues get closed if there has been no activity in the past 28 days. The issue will be automatically closed in 14 days. If you wish to keep this issue open, please add a new comment.

[patrikhuber]

This error occurs if you include spdlog, or a dependency / dependent header that uses spdlog, and don't use target_link_libraries(my-app PRIVATE spdlog::spdlog). What probably happens is that CMake target contains the utf-8 flag (passed down from spdlog or fmt), so naturally, if you don't link against that target in CMake, your code will compile without the utf-8 flag, which then leads to the error.