Fix Issue 18670 - compiler segfault if new on a union type with dip1000

[RazvanN7]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	18670	critical	compiler segfault if new on a union type with dip1000

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "stable + dmd#8095"

[wilzbach]

Hmm SemaphoreCi seems to have troubles with this:

std/path.d(1740): Error: scope variable path assigned to chained with longer lifetime
std/file.d(3003): Error: template instance `std.path.buildNormalizedPath!char` error instantiating

(I restarted the build)

[mathias-lang-sociomantic]

Missing @safe

[wilzbach]

The ICE happened without @safe and I thought the general policy is to copy/paste the submitted samples to the testsuite?

[mathias-lang-sociomantic]

Damn, another case were DIP1000 is not doing what it's supposed to do (nothing DIP1000 related should be checked outside of @safe code).

[RazvanN7]

@wilzbach I have no idea why that error might occur. The code changes affect compilation only if -dip1000 is used and all the check does is avoid calling a method on an empty object. The only thing that comes to mind is a situation in which the patch is applied on a different version of dmd/druntime/phobos then the one I am using.

[wilzbach]

The only thing that comes to mind is a situation in which the patch is applied on a different version of dmd/druntime/phobos then the one I am using.

Yep, SemaphoreCi seems to checkout master - I think #8097 should (hopefully) fix this.