[Issue 13394] invariant fail to link since 2.066 when using separate compilation

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=13394

Kenji Hara <k.hara.pg at gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |link-failure
           Hardware|x86                         |All
                 OS|Mac OS X                    |All

--- Comment #1 from Kenji Hara <k.hara.pg at gmail.com> ---
Introduced in: https://github.com/D-Programming-Language/dmd/pull/3775

====

When a.d is compiled, compiler instantiates Btpl!A and outputs its invariant
objcode to a.obj.

Next b.d is compiled, the `new B` expression instantiates the Btpl!A template
constructor. It implicitly calls the invariant in post-condition, bug Btpl!A is
explicitly instantiated in the non-root module (== a module which not directly
compiled from command line) a. So compiler assumes that the Btpl!A.invariant
objcode will be provided in linking phase and skips its codegen.

However, currently dmd always adds the inferred function attributes into the
symbol name of instantiated functions. Therefore, dmd a.d will emit the objcode
of Btpl!A.invariant with the symbol name:
  _D1a15__T4BtplTC1a1AZ4Btpl11__invariantMxFNaNbNiNfZv

But dmd b.d does not invoke semantic3 of Btpl!A.invariant. Then b.obj refer the
invariant by using the symbol name:
  _D1a15__T4BtplTC1a1AZ4Btpl11__invariantMxFZv
  <-- does not contain the inferred attributes NaNbNiNf

Then link-failure happens.

--