https://issues.dlang.org/show_bug.cgi?id=17287

Илья Ярошенко <ilyayaroshenko@gmail.com> changed:

           What    |Removed                     |Added
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           Keywords|                            |ice-on-valid-code

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https://issues.dlang.org/show_bug.cgi?id=17287

Stefan Koch <uplink.coder@gmail.com> changed:

           What    |Removed                     |Added
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           Keywords|ice-on-valid-code           |accepts-invalid
                 CC|                            |uplink.coder@gmail.com
           Severity|major                       |normal

--- Comment #1 from Stefan Koch <uplink.coder@gmail.com> ---
Apparently no one has written such code.
until now, otherwise this issue would have surfaced sooner.

any length zero array is non-nonsensical in D.

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https://issues.dlang.org/show_bug.cgi?id=17287

ZombineDev <petar.p.kirov@gmail.com> changed:

           What    |Removed                     |Added
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           Keywords|accepts-invalid             |ice-on-valid-code
                 CC|                            |petar.p.kirov@gmail.com
           Hardware|x86                         |All

--- Comment #2 from ZombineDev <petar.p.kirov@gmail.com> ---
@Stefan It easily comes up in generic code when length is based on some
calculation and/or code generation via string mixins For reference see
http://docs.algorithm.dlang.io/latest/mir_ndslice_slice.html#Slice
and browse through the source code (https://github.com/libmir/mir-algorithm).

T[0] is pretty normal if you think about it as struct S { }. If passing around structs without any members works, why wouldn't zero-sized static arrays be ok? Structs without members are invalid in C, but on the contrary are quite common in C++ and similarly D allows them for a reason. See also http://en.cppreference.com/w/cpp/language/ebo, https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html and http://dlang.org/spec/arrays.html:

> A static array with a dimension of 0 is allowed, but no space is allocated for it. It's useful as the last member of a variable length struct, or as the degenerate case of a template expansion.

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https://issues.dlang.org/show_bug.cgi?id=17287

hsteoh@quickfur.ath.cx changed:

           What    |Removed                     |Added
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                 CC|                            |hsteoh@quickfur.ath.cx

--- Comment #3 from hsteoh@quickfur.ath.cx ---
I've used zero-length static arrays at the end of structs before, and they work, for the most part.  I'm surprised having a zero-length member in the middle of a struct causes an ICE, though. Or is it the zero-length ctor parameter that's causing the problem?

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https://issues.dlang.org/show_bug.cgi?id=17287

--- Comment #4 from Илья Ярошенко <ilyayaroshenko@gmail.com> ---
(In reply to hsteoh from comment #3)
> I've used zero-length static arrays at the end of structs before, and they work, for the most part.  I'm surprised having a zero-length member in the middle of a struct causes an ICE, though. Or is it the zero-length ctor parameter that's causing the problem?

It is all factors together. No one line can be removed to reduce this example.

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https://issues.dlang.org/show_bug.cgi?id=17287

--- Comment #5 from kinke@gmx.net ---
(In reply to Илья Ярошенко from comment #4)
> (In reply to hsteoh from comment #3)
> > I've used zero-length static arrays at the end of structs before, and they work, for the most part.  I'm surprised having a zero-length member in the middle of a struct causes an ICE, though. Or is it the zero-length ctor parameter that's causing the problem?
> 
> It is all factors together. No one line can be removed to reduce this example.

We've had the same issue with LDC. Zero-length static arrays are so special because they are the only type with a size of 0. Empty structs have a size of 1. If I recall correctly, we ended up ignoring zero-sized aggregate fields in the backend and passing/returning them as byte (analogous to empty structs).

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https://issues.dlang.org/show_bug.cgi?id=17287

Илья Ярошенко <ilyayaroshenko@gmail.com> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

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