https://issues.dlang.org/show_bug.cgi?id=23638

          Issue ID: 23638
           Summary: [betterC] Better Error Message For Runtime Usage
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: jack@jackstouffer.com

Consider

    extern (C) int main ()
    {
        auto s = "a".idup;
        return 0;
    }

This gives the following

src/druntime/import/object.d(3822): Error: `TypeInfo` cannot be used with
-betterC

This is a trivial example, but when the library is 30 kloc it's a bit harder to track down the offending code from this message. Especially since it doesn't even tell you which runtime function is the problem.

I think the easiest thing to do would be to just add a stack trace like the ones in the error messages for bad template instantiations. Something like

src/druntime/import/object.d(3822): Error: `TypeInfo` cannot be used with
-betterC
Instantiated from here: main.d(3)

It would be nice to have but not necessary to say the name of the runtime function that's attempted to be used.

src/druntime/import/object.d(3822): Error: `TypeInfo` cannot be used with
-betterC
In function dup defined on object.d(3820)
Instantiated from here: main.d(3)

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