https://issues.dlang.org/show_bug.cgi?id=23697

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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           Keywords|                            |accepts-invalid, ImportC
                 CC|                            |ibuclaw@gdcproject.org
           See Also|                            |https://issues.dlang.org/sh
                   |                            |ow_bug.cgi?id=23689
         Depends on|                            |23689


Referenced Issues:

https://issues.dlang.org/show_bug.cgi?id=23689
[Issue 23689] ImportC: C tests in the testsuite are not valid C
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https://issues.dlang.org/show_bug.cgi?id=23697

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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                 CC|ibuclaw@gdcproject.org      |

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https://issues.dlang.org/show_bug.cgi?id=23697

Walter Bright <bugzilla@digitalmars.com> changed:

           What    |Removed                     |Added
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                 CC|                            |bugzilla@digitalmars.com

--- Comment #1 from Walter Bright <bugzilla@digitalmars.com> ---
ImportC, as an extension, allows forward referencing. As it relies on D for the semantic analysis, this is natural. It doesn't cause any harm, though.

I recommend gcc just ignore this test.

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https://issues.dlang.org/show_bug.cgi?id=23697

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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                 CC|                            |ibuclaw@gdcproject.org

--- Comment #2 from Iain Buclaw <ibuclaw@gdcproject.org> ---
(In reply to Walter Bright from comment #1)
> ImportC, as an extension, allows forward referencing. As it relies on D for the semantic analysis, this is natural. It doesn't cause any harm, though.
> 
> I recommend gcc just ignore this test.
The point is just to identify where we're deviating from standard C.  Because if we're not testing ImportC against actual C code, how can we call it a C compiler?

I think having an example of such forward reference on the documentation page would be enough to satisfy this isssue:

https://dlang.org/spec/importc.html#forward-references

Just give friendly names to the first example in this issue.
```
Ta *pa;
struct Sa { int x; };
typedef struct Sa Ta;
```

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https://issues.dlang.org/show_bug.cgi?id=23697

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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          Component|dmd                         |dlang.org
            Summary|compilable/test22705.c:4:1: |ImportC: No examples of
                   |error: unknown type name    |invalid forward references
                   |‘Ta’                        |in C code accepted by
                   |                            |ImportC

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https://issues.dlang.org/show_bug.cgi?id=23697

--- Comment #3 from Iain Buclaw <ibuclaw@gdcproject.org> ---
*** Issue 23720 has been marked as a duplicate of this issue. ***

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https://issues.dlang.org/show_bug.cgi?id=23697

--- Comment #4 from Iain Buclaw <ibuclaw@gdcproject.org> ---
Another example of forward reference code that is accepted by ImportC, rejected by standard C.

```
struct S s;
int* p = &s.t.x;
struct S { int a; struct T t; };
```

Giving both as examples on the ImportC documentation page would be good enough.

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https://issues.dlang.org/show_bug.cgi?id=23697

--- Comment #5 from Iain Buclaw <ibuclaw@gdcproject.org> ---
*** Issue 23721 has been marked as a duplicate of this issue. ***

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https://issues.dlang.org/show_bug.cgi?id=23697

--- Comment #6 from Iain Buclaw <ibuclaw@gdcproject.org> ---
Missing definition of `T` in second example:
```
struct S s;
int* p = &s.t.x;
struct S { int a; struct T t; };
struct T { int b; int x; };
```

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https://issues.dlang.org/show_bug.cgi?id=23697

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
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           Priority|P1                          |P2

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