[Issue 15318] Templates not emitted for two "partial cycles"

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15318

Martin Nowak <code at dawg.eu> changed:

           What    |Removed                     |Added
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                 CC|                            |code at dawg.eu

--- Comment #1 from Martin Nowak <code at dawg.eu> ---
This seems to be a case where the second rule of this issue 14431 fix doesn't
work.
http://forum.dlang.org/post/mailman.697.1440962414.13986.digitalmars-d-bugs@puremagic.com

> If a template is instantiated in non-root module, compiler usually does not have to put it in object file. But if a template is instantiated in both of root and non-root modules which mutually import each other, it needs to placed in objfile.

===

In both of the compilations there is a root and a non-root module instantiating
bar!5. Now unfortunately the compiler decides both times that the non-root
module should do it.
This problem would be solved by my proposal to define a global order for who is
responsible to instantiate a template, by choosing the module with the
lexicographically smaller module name.
https://github.com/D-Programming-Language/dmd/pull/4384#discussion_r29910422
https://issues.dlang.org/show_bug.cgi?id=14431#c12

This would establish a stable order between B and C, and no matter how you
compile them, B gets to instantiate the template.

===

An intermediate workaround for your problem is to use the -allinst switch, even
though it slows down compilation a lot. You can also compile each module
separately in which case both B and C get the instance (in general this is even
slower than -allinst).

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