Bug 22041 – SumType assignments should work with pointers in @safe code

Pretty much self-explainatory. This should work in @safe code: ```d alias FooBar = SumType!(int*); auto foobar = FooBar(new int); foobar = FooBar(new int); ```

@ljmf00 created dlang/phobos pull request #8146 "sumtype: remove forced @system for opAssign preventing @safe code" fixing this issue: - sumtype: remove forced @system for opAssign preventing @safe code Fixes #22041 . D programming language is moving towards @safe code and introducing new @system code makes std.sumtype fundamentally useless when using it under @safe code. Forcing @system when the users are using pointers is just wrong. The simple example to prove it is the following: ```d void main() @safe { int* thisIsNotUnsafe = new int; } ``` Using pointers in D is not necessarily @system. Moreover, this code is preventing the following code to compile in @safe: ```d alias FooBar = SumType!string; auto foobar = FooBar("foo"); foobar = FooBar("bar"); ``` Signed-off-by: Luís Ferreira <[email protected]> https://github.com/dlang/phobos/pull/8146

This would allow undefined behavior in @safe code: --- int n; int example() @safe { SumType!(int*, int) x = &n; return x.match!( (int n) => n, (ref int* p) { x = 123456789; // overwrites p (currently @system) return *p; // kaboom } ); } ---