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digitalmars.D.ldc - unresolved external symbol in BetterC

reply Marcel <marcelpi97 gmail.com> writes:
I've been getting some weird linker errors around main() when I 
declare a struct with a destructor. Is it possible that exception 
code is being generated even though I have the -betterC flag 
enabled?

//Example code:
extern(C) void main()
{
	auto window = Window("Hello", 0, 0, 800, 600);
	while(window.IsLive)
		window.Update;
}
Dec 08 2019
next sibling parent reply Mike Parker <aldacron gmail.com> writes:
On Sunday, 8 December 2019 at 19:29:23 UTC, Marcel wrote:

 I've been getting some weird linker errors around main() when I 
 declare a struct with a destructor. Is it possible that 
 exception code is being generated even though I have the 
 -betterC flag enabled?

 //Example code:
 extern(C) void main()
 {
 	auto window = Window("Hello", 0, 0, 800, 600);
 	while(window.IsLive)
 		window.Update;
 }


Struct destructors should work in betterC. It would be helpful if 
you can paste the errors.
Dec 08 2019
parent reply Marcel <marcelpi97 gmail.com> writes:
On Sunday, 8 December 2019 at 19:36:40 UTC, Mike Parker wrote:

 Struct destructors should work in betterC. It would be helpful 
 if you can paste the errors.


extern(C) void main()
{
	auto pool = ObjectPool!(int)(100);
	auto a = pool.Acquire;
	pool.Release(*a);
}

This code generates the two following errors:

1>Test.obj : error LNK2019: unresolved external symbol 
_d_enter_cleanup referenced in function "?dtor$5 ?0?"ref 
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array.opAssign(const(Collections.Arrays.Array!(Collections.ObjectPo
ls.ObjectPool!(int, Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array))"
(_D11Collections6Arrays__T5ArrayTSQBf11ObjectPools__T10ObjectPoolTiTS6Memory10Allocators16DefaultAllocatorZQCc5EntryTQBxZQDr8opAssignMFNcxSQFgQEw__TQEsTQEpTQDkZQFeZSQGgQFw__TQ
sTQFpTQEkZQGe) 4HA" (?dtor$5 ?0?"ref
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array.opAssign(const(Collections.Arrays.Array!(Collections.ObjectPo
ls.ObjectPool!(int, Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array))"
(_D11Collections6Arrays__T5ArrayTSQBf11ObjectPools__T10ObjectPoolTiTS6Memory10Allocators16DefaultAllocatorZQCc5EntryTQBxZQDr8opAssignMFNcxSQFgQEw__TQEsTQEpTQDkZQFeZSQGgQFw__TQFsTQFpTQEkZQGe) 4HA)

1>Test.obj : error LNK2019: unresolved external symbol 
_d_leave_cleanup referenced in function "?dtor$5 ?0?"ref 
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array.opAssign(const(Collections.Arrays.Array!(Collections.ObjectPo
ls.ObjectPool!(int, Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array))"
(_D11Collections6Arrays__T5ArrayTSQBf11ObjectPools__T10ObjectPoolTiTS6Memory10Allocators16DefaultAllocatorZQCc5EntryTQBxZQDr8opAssignMFNcxSQFgQEw__TQEsTQEpTQDkZQFeZSQGgQFw__TQ
sTQFpTQEkZQGe) 4HA" (?dtor$5 ?0?"ref
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array
Collections.Arrays.Array!(Collections.ObjectPools.ObjectPool!(int,
Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array.opAssign(const(Collections.Arrays.Array!(Collections.ObjectPo
ls.ObjectPool!(int, Memory.Allocators.DefaultAllocator).ObjectPool.Entry,
Memory.Allocators.DefaultAllocator).Array))"
(_D11Collections6Arrays__T5ArrayTSQBf11ObjectPools__T10ObjectPoolTiTS6Memory10Allocators16DefaultAllocatorZQCc5EntryTQBxZQDr8opAssignMFNcxSQFgQEw__TQEsTQEpTQDkZQFeZSQGgQFw__TQFsTQFpTQEkZQGe) 4HA)
Dec 08 2019
parent Marcel <marcelpi97 gmail.com> writes:
On Sunday, 8 December 2019 at 19:57:11 UTC, Marcel wrote:

 On Sunday, 8 December 2019 at 19:36:40 UTC, Mike Parker wrote:

 [...]


 extern(C) void main()
 {
 	auto pool = ObjectPool!(int)(100);
 	auto a = pool.Acquire;
 	pool.Release(*a);
 }

 [...]


Ok, I found a way to make this work by writing "nothrow:" inside 
each struct and module. Is this normal?
Dec 08 2019
prev sibling parent reply kinke <noone nowhere.com> writes:
On Sunday, 8 December 2019 at 19:29:23 UTC, Marcel wrote:

 Is it possible that exception code is being generated even 
 though I have the -betterC flag enabled?


Yes, a cleanup/finally is used, apparently in an opAssign. - 
These 2 symbols are apparently used to prevent too aggressive 
LLVM optimizations and are normally provided in druntime here 
[1]; you can add the 2 one-liners manually in a betterC project.

[1] 
https://github.com/ldc-developers/druntime/blob/d363d27e119e7cc41b8fd5ef2145d8a7ad140080/src/ldc/eh_msvc.d#L593-L606
Dec 08 2019
parent Marcel <marcelpi97 gmail.com> writes:
On Sunday, 8 December 2019 at 20:58:44 UTC, kinke wrote:

 On Sunday, 8 December 2019 at 19:29:23 UTC, Marcel wrote:

 Is it possible that exception code is being generated even 
 though I have the -betterC flag enabled?


 Yes, a cleanup/finally is used, apparently in an opAssign. - 
 These 2 symbols are apparently used to prevent too aggressive 
 LLVM optimizations and are normally provided in druntime here 
 [1]; you can add the 2 one-liners manually in a betterC project.

 [1] 
 https://github.com/ldc-developers/druntime/blob/d363d27e119e7cc41b8fd5ef2145d8a7ad140080/src/ldc/eh_msvc.d#L593-L606


Perfect! Thank you very much!
Dec 08 2019