<random>: piecewise_linear_distribution<T>::param_type should not inherit from discrete_distribution<size_t>::param_type #1600
Description
Describe the bug
Currently, piecewise_constant_distribution<T>::param_type and piecewise_linear_distribution<T>::param_type inherit from discrete_distribution<size_t>::param_type, although conceptually they are unrelated types. piecewise_linear_distribution<T>::param_type even breaks the invariants of its base class.
Invalid code could compile and run unexpectedly, and return nonsense.
Command-line test case
C:\Users\He\source\test>type random_param_inherit.cpp
#include <cstddef>
#include <random>
using namespace std;
int main() {
piecewise_linear_distribution<> d1;
discrete_distribution<size_t> d2(d1.param());
return 0;
}C:\Users\He\source\test>cl /EHsc /W4 /WX random_param_inherit.cpp
用于 x64 的 Microsoft (R) C/C++ 优化编译器 19.28.29812 版
版权所有(C) Microsoft Corporation。保留所有权利。
random_param_inherit.cpp
Microsoft (R) Incremental Linker Version 14.28.29812.0
Copyright (C) Microsoft Corporation. All rights reserved.
/out:random_param_inherit.exe
random_param_inherit.obj
Expected behavior
The test code should not compile.
STL version
https://github.com/microsoft/STL/commit/721e3ad8952fce3447916ecdbff3863043686fa1