Define FMT_CONSTEVAL as inline in libenvpp.cmake for compatibility.

Author: allnes

cmake/libenvpp.cmake

@@ -10,7 +10,7 @@ ExternalProject_Add(ppc_libenvpp
         CONFIGURE_COMMAND "${CMAKE_COMMAND}" -S "${CMAKE_SOURCE_DIR}/3rdparty/libenvpp/" -B "${CMAKE_CURRENT_BINARY_DIR}/ppc_libenvpp/build/"
         -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -G${CMAKE_GENERATOR} -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
         -D CMAKE_C_COMPILER_LAUNCHER=${CMAKE_C_COMPILER_LAUNCHER} -D CMAKE_CXX_COMPILER_LAUNCHER=${CMAKE_CXX_COMPILER_LAUNCHER}
-        -D CMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD} -D CMAKE_CXX_STANDARD_REQUIRED=ON
+        -D CMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD} -D CMAKE_CXX_STANDARD_REQUIRED=ON -DFMT_CONSTEVAL=inline
         BUILD_COMMAND     "${CMAKE_COMMAND}" --build "${CMAKE_CURRENT_BINARY_DIR}/ppc_libenvpp/build" --config ${CMAKE_BUILD_TYPE} --parallel
         INSTALL_COMMAND   "${CMAKE_COMMAND}" --install "${CMAKE_CURRENT_BINARY_DIR}/ppc_libenvpp/build" --prefix "${CMAKE_CURRENT_BINARY_DIR}/ppc_libenvpp/install")
 
@@ -25,4 +25,6 @@ if(MSVC)
     set(PPC_ENVPP_LIB_NAME libenvpp)
 else()
     set(PPC_ENVPP_LIB_NAME envpp)
-endif ()
+endif ()
+
+add_compile_definitions(FMT_CONSTEVAL=inline)