[Feature Request] RGBLINK should notify a user when a label exists but is not exported.

[eievui5]

Currently RGBLINK will fail if Foo is defined in another translation unit but is not exported. This error could be made more useful if RGBLINK reported the locations of the non-exported symbols so that the user could export them.

[Rangi42]

The error message is just "Unknown symbol"; rgblink doesn't know that the symbol is defined in another translation unit, and a symbol with that name may be defined in none or in more than one.

[ISSOtm]

The request is for

; a.asm
Label:

; b.asm
ld hl, Label

...to have the error message from b.o mention that a symbol with the same name is defined in a.o but is unreachable. It would be a good idea to mention the source file as well, a.asm.

In case there are multiple, well, the multiple options would be mentioned. Perhas we'd want to cap the number of options, and sum then up to "and N more"?

If there are none, then it's truly an unknown symbol, and the current error is perfectly sufficient.

[Rangi42]

I think users would find it pretty frustrating if they saw an error like:

error: b.asm(2): Unknown symbol "Label"
    A label "Label" is defined but not exported at a.asm(2)

because the obvious next question is "if rgblink knows where the one possible Label is, why doesn't it use it!?"

This would be a much happier change when there are multiple possibilities:

error: b.asm(2): Unknown symbol "Label"
    A label "Label" is defined but not exported at a.asm(2)
    A label "Label" is defined but not exported at c.asm(3)
    A constant "Label" is defined but not exported at q.asm(5)

[ISSOtm]

Perhaps this could reduce frustration:

error: b.asm(2): Unknown symbol "Label"
help: The symbol is not defined in the same object file, and symbols from other object files can only be used if exported.
    A label "Label" is defined at a.asm(2), but not exported