Simple code compiles with latest visual studio C++ compiler but not with Intel 2025 C++ compiler

Olórin — Thu, 31 Jul 2025 15:37:13 GMT

I have a simple code : in toto.ixx file :

module; #include <iostream> #include <typeinfo> #include <utility> export module math; template <typename T> auto showType(T&&t) { return typeid(std::forward<T>(t)).name(); } export namespace math { template <typename T, typename T2> auto sum(T fir, T2 sec) { auto res = fir + sec; return std::make_pair(res, showType(res)); } }

and in ConsoleApplication3.cpp :

#include <iostream> import math; int main() { auto [val, message] = math::sum(2000, 3.14159); std::cout << "math::sum(2000, 11) : " << val << "; type: " << message << '\n'; }

This compiles and executes fine with latest Visual Studio Professional 2022 C++ compiler while it doesn't compile with Intel C++ 2025 compiler, the build output being :

1>------ Build started: Project: ConsoleApplication3, Configuration: Debug x64 ------ 1>C:\pah\to\solutions\ConsoleApplication3\ConsoleApplication3\ConsoleApplication3.cpp(2,8): : error : module 'math' not found 1> 2 | import math; 1> | ~~~~~~~^~~~ 1>1 error generated. 1>Done building project "ConsoleApplication3.vcxproj" -- FAILED. ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== ========== Build completed at 17:32 and took 02.479 seconds ==========

Of course "Preview - Features from the Latest C++ Working Draft (/std:c++latest)" is activated.

What is happening ?

topic Simple code compiles with latest visual studio C++ compiler but not with Intel 2025 C++ compiler in Intel® oneAPI DPC++/C++ Compiler

Simple code compiles with latest visual studio C++ compiler but not with Intel 2025 C++ compiler