Missing include

[cloudhan]

If you add target_compile_definitions(yomm2 PUBLIC YOMM2_ENABLE_TRACE=0) to top level CMakeLists.txt, and build the project's example, it will results

D:\yomm2\src\yomm2.cpp(858,42): error C2079: 'discard_log' uses undefined class 'std::basic_ostringstream<char,std::char_traits<char>,std::allocator<char>>' [D:\yomm2\build\src\yomm2.vcxproj]
D:\yomm2\src\yomm2.cpp(864,50): error C2446: ':': no conversion from 'std::ostringstream' to 'std::ostream' [D:\yomm2\build\src\yomm2.vcxproj]

Compiler:

Microsoft (R) C/C++ Optimizing Compiler Version 19.26.28806 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

[jll63]

Thanks for the report and the fix.