[Issue 24469] non-constant nested delegate literal expression - Error on delegates causing memory corruption

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24469

kinke  changed:

   What|Removed |Added

   Severity|critical|regression

--- Comment #3 from kinke  ---
Oh and this is a regression according to run.dlang.io - up to v2.078, DMD
issued a 'Error: non-constant nested delegate literal expression `__lambda2`'
error too; since v2.079, it allows compilation but crashes at runtime.

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[Issue 24469] non-constant nested delegate literal expression - Error on delegates causing memory corruption

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24469

kinke  changed:

   What|Removed |Added

 CC||ki...@gmx.net

--- Comment #2 from kinke  ---
Full example, showing the crash with DMD (LDC issues a compile error instead -
'Error: non-constant nested delegate literal expression `__lambda2`'):

```
struct ExistenceChecker
{
bool delegate() checkExistenceFn;
}

ExistenceChecker makeExistenceChecker(string gemName)
{
return ExistenceChecker(() => gemName == "dummy");
}

auto checker = makeExistenceChecker("test"); // => invalid non-constant
initializer

void main()
{
assert(!checker.checkExistenceFn());
}
```

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[Issue 24469] non-constant nested delegate literal expression - Error on delegates causing memory corruption

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24469

--- Comment #1 from Marcelo Silva Nascimento Mancini  
---
I was able to reduce the bug:

```d
struct ExistenceChecker
{
///Optional. 
bool delegate() checkExistenceFn;

}
ExistenceChecker makeExistenceChecker(string gemName)
{
return ExistenceChecker(()
{
return executeShell("gem list | grep "~gemName).status == 0;
});
}

ExistenceChecker[] chks = [
makeExistenceChecker("test")
];
```

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