Bug 19439 – Make __traits(getAliasThis) return empty tuple for non-aggregate types

It is frequently necessary to verify that aliasing is not occurring. Checking that the result of __traits(getAliasThis) has length 0 is a concise and natural way of doing this. Unfortunately it is currently disallowed to `getAliasThis` a non-aggregate type. Returning an empty tuple instead of raising a compile-time error would also be convenient for using `getAliasThis` in type-generic code. It should not make DMD slower to change this behavior: not raising an error slightly simplifies the logic.

Commit pushed to master at https://github.com/dlang/dmd https://github.com/dlang/dmd/commit/7d3a7631b59501ae9ae85ec9b7a43529d50b9dd9 Fix Issue 19439 - Make __traits(getAliasThis) return empty tuple for non-aggregate types

Commit pushed to master at https://github.com/dlang/dlang.org https://github.com/dlang/dlang.org/commit/8e32471a33ebf1f445fb377021308d7ed00d1f35 Merge pull request #2517 from n8sh/issue-19439 Update getAliasThis documentation per issue 19439 merged-on-behalf-of: Petar Kirov <[email protected]>