[fmt] build failure: clang++: error: no such file or directory: '/utf-8'

[marleeeeeey]

Operating system

Windows 11 23H2 (OS Build 22631.4037)

Compiler

clang version 18.1.8
cmake version 3.30.3

Steps to reproduce the behavior

Step 1. cmake configure

Commands:

git clone --branch 2024.08.23 --single-branch https://github.com/microsoft/vcpkg
.\vcpkg\bootstrap-vcpkg.bat
.\vcpkg\vcpkg install --triplet=x64-windows

cmake -S . -B build --preset use_vcpkg -GNinja -DCMAKE_CXX_COMPILER=clang++ --trace

Output:

Pay attention to this argument: \$<\$<COMPILE_LANGUAGE:CXX>:/utf-8>.
Looks like error comes from: vcpkg\ports\folly\fix-fmt11-cmake.patch:
string(REPLACE "<$<COMPILE_LANGUAGE:CXX>:/utf-8>" "/utf-8" cflags "${cflags}")

C:/dev/vcpkg_error_minimal_example/build/vcpkg_installed/x64-windows/share/fmt/fmt-targets.cmake(60):  set_target_properties(fmt::fmt PROPERTIES INTERFACE_COMPILE_DEFINITIONS FMT_SHARED INTERFACE_COMPILE_FEATURES cxx_std_11 INTERFACE_COMPILE_OPTIONS \$<\$<COMPILE_LANGUAGE:CXX>:/utf-8> INTERFACE_INCLUDE_DIRECTORIES ${_IMPORT_PREFIX}/include )

Step 2. cmake build -> error

Commands:

cmake --build build -- -k 0

Output:

[1/2] Building CXX object CMakeFiles/main_cpp.dir/main.cpp.obj
FAILED: CMakeFiles/main_cpp.dir/main.cpp.obj
C:\PROGRA~1\LLVM\bin\CLANG_~1.EXE -DFMT_SHARED -DSPDLOG_COMPILED_LIB -DSPDLOG_FMT_EXTERNAL -DSPDLOG_SHARED_LIB -isystem C:/dev/vcpkg_error_minimal_example/build/vcpkg_installed/x64-windows/include -O0 -g -Xclang -gcodeview -D_DEBUG -D_DLL -D_MT -Xclang --dependent-lib=msvcrtd /utf-8 -MD -MT CMakeFiles/main_cpp.dir/main.cpp.obj -MF CMakeFiles\main_cpp.dir\main.cpp.obj.d -o CMakeFiles/main_cpp.dir/main.cpp.obj -c C:/dev/vcpkg_error_minimal_example/main.cpp
clang++: error: no such file or directory: '/utf-8'
ninja: build stopped: cannot make progress due to previous errors.

Files

CMakePreset.json

{
    "version": 8,
    "configurePresets": [
        {
            "name": "use_vcpkg",
            "cacheVariables": {
                "CMAKE_TOOLCHAIN_FILE": "vcpkg/scripts/buildsystems/vcpkg.cmake"
            }
        }
    ]
}

vcpkg.json

{
  "dependencies": [
    "spdlog"
  ]
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.15)
project(main_cpp)
find_package(spdlog CONFIG REQUIRED)
add_executable(main_cpp main.cpp)
target_link_libraries(main_cpp PRIVATE spdlog::spdlog)

main.cpp

int main() {}

Failure logs

[1/2] Building CXX object CMakeFiles/main_cpp.dir/main.cpp.obj
FAILED: CMakeFiles/main_cpp.dir/main.cpp.obj
C:\PROGRA~1\LLVM\bin\CLANG_~1.EXE -DFMT_SHARED -DSPDLOG_COMPILED_LIB -DSPDLOG_FMT_EXTERNAL -DSPDLOG_SHARED_LIB -isystem C:/dev/vcpkg_error_minimal_example/build/vcpkg_installed/x64-windows/include -O0 -g -Xclang -gcodeview -D_DEBUG -D_DLL -D_MT -Xclang --dependent-lib=msvcrtd /utf-8 -MD -MT CMakeFiles/main_cpp.dir/main.cpp.obj -MF CMakeFiles\main_cpp.dir\main.cpp.obj.d -o CMakeFiles/main_cpp.dir/main.cpp.obj -c C:/dev/vcpkg_error_minimal_example/main.cpp
clang++: error: no such file or directory: '/utf-8'
ninja: build stopped: cannot make progress due to previous errors.

Additional context

No response

[JonLiu1993]

Fixing by #40944