Bug 21035 – wrong code when uses struct's methods of .init value

struct CNB { string _separator = "-"; char[64] data = '\0'; /// @disable this(this); @safe pure @nogc: /// ref CNB append(scope const(char)[] str) scope return { data[0 .. str.length] = str; return this; } } extern(C) void main() { auto id = CNB .init .append("USD.LIBOR.1D") .data; } $ dmd -inline -betterC -run test.d -betterC is optional

How does the wrong-ness of this code manifest?

(In reply to Stefan Koch from comment #1) > How does the wrong-ness of this code manifest? It fails to execute with exit code -11

What happens is that a `memcpy` fails which seems to be done executing `data[0 .. str.length] = str` why that happens is still under investigation

Aren't the ".init" values read only? The append tries to change the "data" member of the initializer, which results in an memory write error.

(In reply to KytoDragon from comment #4) > Aren't the ".init" values read only? The append tries to change the "data" > member of the initializer, which results in an memory write error. D doesn't prohibit to call methods of right hand side values.

Definitely an accepts-invalid. Trying to bind `.init` to a mutable lvalue should not be allowed.

I don't see where this would be invalid - `CNB.init` is a new rvalue (analogous to `CNB()`), `append` returns it as lvalue (allowed IIRC for DotIdExpressions), and then its `data` buffer is copied to the `id` local. Works fine with LDC.

It seems that the inliner somehow screws up the code. Without -inline code runs successfully.

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