pointer types in unsafe code aren't supported

[snikeguo]

Tool

Visual Studio extension

Description

c# code:
byte *ptr =(byte *)0x80000000;
byte *d=*ptr;

build failed:
pointer types in unsafe code aren't supported

How to reproduce

No response

Expected behaviour

No response

Screenshots

No response

Aditional context

No response

[josesimoes]

Hello @snikeguo! Thanks for reaching out.
This is not a bug, it's by design. We don't have any plans to add support for these.

[snikeguo]

@josesimoes

[snikeguo]

I want to use c# to write drivers:
u32 *reg= (u32*) 0x12345678; var oldvalue=*reg; *reg=0x87654321;
Are you worried that others can read the firmware?

[josesimoes]

Allowing this opens the possibility to read/write from/to memory and even registers.
That has inpact on security and privacy not to mention that it can render a system unusable or unstable by allowing to change any content addressable in memory.

[snikeguo]

I think this function can be added, and the right to select is on the user. Just like C ++: You can not use the meta -programming function, but I can't without it!There are 20%of senior users using it.

[josesimoes]

There's more to it than just "add it". I haven't wrote that it's not possible, rather that's not on our plans to implement it. For the reasons mentioned.
I don't have access to the same statistics that you have, obviously. 😅 But from the output of nanoFramework community, as far as I can recall, you're the first and only one to request it.

Can you elaborate on your usage scenario please?

[Tajbiul-Rawol]

Why is there no plan to support it? I mean why limit the usage of pointers and go really low and instead worry about safety? Isn't this the point to allow the flexibility to write safe code with C# but you can also shoot yourself in the foot if you want to?

[Ellerbach]

Why is there no plan to support it?

Because of the way the stack is managed.

I mean why limit the usage of pointers and go really low and instead worry about safety?

For this, you can run your own C/C++ code and use interop to consume it in C#. All nanoFramework is built like this!