C 20 Modules std.ixx STL Static/Global Scope References-CodePudding

Following instructions by Microsoft, I couldn't get the std module to build and not have a versioning error, so I went ahead and just added the file:

C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.35.32213\modules\std.ixx

to my project and I import it into my module interface files. My only issue is I can't access ::localtime_s because it is one of the static-inline/global functions not in the std namespace. Including <time.h> in the global module space creates issues with macro redefinitions. Is there something I am missing?

export module MyModule;

import std;

export namespace nspace1 {

    void TimeFunction();

}

namespace nspace1 {

    void TimeFunction()
    {
        std::time_t t = std::time(nullptr);

        std::tm* now{};

        void* result = ::localtime_s(now, &t); <== dne

    }

}

The intellisense error is it is not found in the global space which makes sense for localtime_s because it is static, but _localtime64_s is just global and it says the same thing. Dropping the double colons just changes the error message to cannot be found.

CodePudding user response：

The following code builds ok on my machine.

(Version 17.5.0 Preview 3.0)

import std; is a C 23 feature. I hope vendor support is getting better.

module;

#include <time.h>

export module MyModule;

import std;

export namespace nspace1 {

    void TimeFunction();

}

namespace nspace1 {

    void TimeFunction()
    {
        std::time_t t = std::time(nullptr);

        std::tm* now{};

        auto result = ::localtime_s(now, &t);
        //auto result = localtime_s(now, &t); // ok, too

    }
}