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digitalmars.D - workaround for `The module 'foo.bar' is already defined` when

reply Timothee Cour via Digitalmars-d <digitalmars-d puremagic.com> writes:
```
dmd -shared -oflibfoo.so a1.d a2.d
dmd -ofmain -L-lfoo a2.d main.d
./main
```
gives runtime error: `The module 'foo.bar' is already defined in 'main'`

How would I work around this error?

Use case: allow partial recompilation of a binary without rebuilding
everything to optimize compile time for fast edit debug cycles.
Jun 10 2017
parent reply timotheecour <timothee.cour2 gmail.com> writes:
On Sunday, 11 June 2017 at 05:21:23 UTC, Timothee Cour wrote:

 ```


NOTE: this is on linux, and the above simple case doesn't 
reproduce
the error, but my test case is similar albeit from a larger 
program
that's hard to reduce.

the code that crashes is in druntime:
/**
  * Check for module collisions. A module in a shared library 
collides
  * with an existing module if it's ModuleInfo is interposed 
(search
  * symbol interposition) by another DSO.  Therefor two modules 
with the
  * same name do not collide if their DSOs are in separate symbol 
resolution
  * chains.
  */
void checkModuleCollisions(in ref dl_phdr_info info, in
immutable(ModuleInfo)*[] modules,
                            in void[] copyRelocSection) nothrow

Could someone please explain:

* what that means
* what's the simplest example that would exhibit this error
* what's a workaround ? (where i want to do partial recompilation)
Jun 11 2017
parent timotheecour <timothee.cour2 gmail.com> writes:
On Sunday, 11 June 2017 at 07:09:33 UTC, timotheecour wrote:

 On Sunday, 11 June 2017 at 05:21:23 UTC, Timothee Cour wrote:

 [...]


 NOTE: this is on linux, and the above simple case doesn't 
 reproduce
 the error, but my test case is similar albeit from a larger 
 program
 that's hard to reduce.

 [...]


On Sunday, 11 June 2017 at 07:09:33 UTC, timotheecour wrote:

Removing `-l:libphobos2.so.0.72` from dub.json "lflags" fixed the 
issue, but I'd like to understand why?
Jun 11 2017