[Issue 19091] __traits(compiles) and error in templated structs leads to missing symbol

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19091

--- Comment #4 from FeepingCreature <default_357-line at yahoo.de> ---
A different way of provoking the same effect:

```
struct Struct() {
    static void missing() { } // this will be missing from the linker
    void fun() { error; } // will provoke an error if attempted to compile
}

void helper1()() { Struct!().missing; }

void helper2()() { helper1(); }

void main() {
    static assert(!__traits(compiles, helper2()));
    helper1();
}
```

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