Bug 10928 – Fails to create closures that reference structs with dtor

To make example real simple: struct D{ int x; ~this() { } } void foo(D bar) { (){ bar.x++; }(); } void main() { foo(D.init); } Note that even though there is no need for allocating closure at all. Compiler should deal with such cases by tiying the lifetime of dtor-able variables to that of a closure if one is indeed required. This is critical as std.array.array and other functions started using internal lambdas for trusted blocks making use of any RefCounted range impossible.

Error message: d_test.d(10): Error: variable d_test.foo.bar has scoped destruction, cannot build closure

For reference, an "in-the-wild" example of such an error: http://forum.dlang.org/post/[email protected] http://forum.dlang.org/thread/[email protected] This is a concern as it potentially blocks the ability to move forward with necessary redesign work on random number generation in Phobos.

(In reply to comment #2) > For reference, an "in-the-wild" example of such an error: > http://forum.dlang.org/post/[email protected] > http://forum.dlang.org/thread/[email protected] > > This is a concern as it potentially blocks the ability to move forward with > necessary redesign work on random number generation in Phobos. Currently, a *workaround* is to avoid lambdas in favor of named: //---- struct D { int x; ~this() { } } void foo(D bar) { void do_it(){ bar.x++; } do_it(); } void main() { foo(D.init); } //----

Commits pushed to master at https://github.com/D-Programming-Language/phobos https://github.com/D-Programming-Language/phobos/commit/8d50d807bed69ee9b339de81ee50f3c105ef3900 sidestep issue 10928 https://github.com/D-Programming-Language/phobos/commit/01a2bdb02e45f61ed3773d40d2aac4dadcb2a767 Merge pull request #1535 from blackwhale/fix-lambda Sidestep issue 10928

Also see bug 11382

Commit pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/4b9df682679b7792aa48a32aa343d3dd63a6a3ad fix Issue 10928 - Fails to create closures that reference structs with dtor