• Iain Buclaw (28/28) Aug 17 2012 Discovered this through some other issue when finishing up the
• Iain Buclaw (2/5) Aug 17 2012 s/scalar/non-scalar/
• bearophile (4/6) Aug 17 2012 Accepting the cast of an AA to void* seems bad.
• Richard Webb (4/4) Aug 18 2012 fwiw, I raised a bug about this on Orange a while back:
• David Nadlinger (6/18) Aug 18 2012 I also once encountered some cases where the DMD frontend would

"Iain Buclaw" <ibuclaw ubuntu.com> writes:

Discovered this through some other issue when finishing up the 
latest frontend merge.


In the following example, I feel that this should not compile at 
all.

void main()
{
   int[int] a;
   void* b = cast(void*)a;
}


Given that the definition of an AA is (as defined in rt.aaA):

struct AA
{
     void* a;
}


Similarly for this code:

void main()
{
   int[int] a;
   void* b;
   a = cast(int[int]) b;   // fails
   a = cast(int[int]) &b;  // works
}

Correct me if I'm wrong, but both examples should warrant bug 
reports.


NB: These examples don't compile on GDC because of the safe 
guards from directly converting between scalar and pointer types.


Regards
Iain

"Iain Buclaw" <ibuclaw ubuntu.com> writes:

On Friday, 17 August 2012 at 22:15:10 UTC, Iain Buclaw wrote:

 NB: These examples don't compile on GDC because of the safe 
 guards from directly converting between scalar and pointer 
 types.

s/scalar/non-scalar/

"bearophile" <bearophileHUGS lycos.com> writes:

Iain Buclaw:

 Correct me if I'm wrong, but both examples should warrant bug 
 reports.

Accepting the cast of an AA to void* seems bad.

Bye,
bearophile

"Richard Webb" <webby beardmouse.org.uk> writes:

fwiw, I raised a bug about this on Orange a while back: 
https://github.com/jacob-carlborg/orange/issues/17.

I thought it a bit odd that it compiled in DMD at the time, but i 
don't think i opened a bug about it.

"David Nadlinger" <see klickverbot.at> writes:

On Friday, 17 August 2012 at 22:15:10 UTC, Iain Buclaw wrote:
 In the following example, I feel that this should not compile 
 at all.

 void main()
 {
   int[int] a;
   void* b = cast(void*)a;
 }


 Given that the definition of an AA is (as defined in rt.aaA):

 struct AA
 {
     void* a;
 }

I also once encountered some cases where the DMD frontend would 
allow conversions between structs and scalar types or other 
unrelated structs which happened to have the same member layout 
– which broke LDC, as the LLVM IR is typed.

David