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

--- Comment #1 from FeepingCreature <default_357-line@yahoo.de> ---
Note that __traits(compiles) evaluates to true?!

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

--- Comment #2 from FeepingCreature <default_357-line@yahoo.de> ---
Found a new version of this bug:

```
void early()() { Struct!() var; }

struct Struct() { void fun() { error; } }

void main() {
    void helper()() { early; }

    static assert(!__traits(compiles, helper()));
    helper();
}
```

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

--- Comment #3 from FeepingCreature <default_357-line@yahoo.de> ---
Correction, sorry; didn't pay attention and accidentally pasted a working version. This one properly linker errors:

```
void early()() { auto var = Struct!()(0); }

struct Struct() { this(int) { } void fun() { error; } }

void main() {
    void helper()() { early!(); }

    static assert(!__traits(compiles, helper()));
    helper();
}
```

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

--- Comment #4 from FeepingCreature <default_357-line@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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https://issues.dlang.org/show_bug.cgi?id=19091

Mario Kroeplin <kroeplin.d@googlemail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |industry
                 CC|                            |kroeplin.d@googlemail.com

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

--- Comment #5 from FeepingCreature <default_357-line@yahoo.de> ---
https://issues.dlang.org/show_bug.cgi?id=21235 might be the same bug? I don't know.

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

FeepingCreature <default_357-line@yahoo.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|enhancement                 |normal

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

--- Comment #6 from FeepingCreature <default_357-line@yahoo.de> ---
Update: version that makes it clearer what happens:

```
struct Template {
    void opEquals(U, this TA)(U) {
        pragma(msg, "Template.opEquals!(" ~ U.stringof ~ ", " ~ TA.stringof ~
")");
        foo();
    }
}

void foo()() {
    static assert(false); // foo() fails xeq semantic3 while gagged
    bar!();
}

// this is the symbol that sticks around and references foo().
// Despite foo() erroring, bar() is not errored and emits normally.
void bar()() {
    pragma(msg, "bar()");
    foo();
}

void main() { }
```

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

--- Comment #7 from FeepingCreature <default_357-line@yahoo.de> ---
Unified with what I'm learning from the testcase from 21235:

```
// gag the foo error
static assert(!__traits(compiles, foo()));

void foo()() {
    static assert(false);
    bar!();
}

// foo() is not errored while bar compiles? because circular
void bar()() { foo(); }

// no error
void main() { bar(); }
```

I don't think we'll get it smaller than this.

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

--- Comment #8 from FeepingCreature <default_357-line@yahoo.de> ---
*** Issue 21235 has been marked as a duplicate of this issue. ***

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