Incorrect access check within requires-clause of module-imported member function template

[cpplearner]

Issue Summary

In a call to a member function template of a class imported from (MSVC-generated) IFC file, EDG incorrectly believes that a private member in the requires-clause is inaccessible.

Since this pattern is used by MSVC STL's std::ranges::begin, this bug affects most uses of intelliSense with import std; and std::ranges.

Reproducing Source Code

mod1.ixx (compiled with MSVC's cl.exe /c /std:c++20 mod1.ixx):

export module mod1;

export struct begin_fn {
private:
    static constexpr int choice = 1;

public:
    template<class T>
        requires (choice != 0)
    int operator()(T) { return 42; }
};

example.cxx (compiled with \CXX\edgcpp-compiler\build\msvc-release\bin\cpfe.exe --ms_c++20 --modules example.cxx):

import mod1;

int main() {
    begin_fn{}(1);
}

Command-line Options

cpfe.exe --ms_c++20 --modules example.cxx

Type of Issue

[Front End] This code SHOULD compile with these options.

Additional Details

The IFC file is generated by MSVC Compiler Version 19.52.36815 for x64 (PREVIEW). The file example.cxx compiles fine with cl.exe /std:c++20 example.cxx and fails to compile with cl.exe /BE /std:c++20 example.cxx.

Reproducing (Standard) Configuration(s)

windows-msvc-release

Reproducing (Non-standard) Configuration

No response

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• I have checked open issues and existing discussions before filing this report.
• The reproducing source code that I have provided does not depend on headers that I have not included with my submission.
• I have reduced the reproducing source code to the best of my ability.
• I have selected at least one standard configuration or uploaded a non-standard configuration dump.
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[cpplearner]

mod1.ifc.zip