[Issue 281] New: dmd generates the object code ld cannot link when working with templates

[Sean Kelly]

d-bugmail at puremagic.com wrote:
> 
> It compiles fine, but ld generates following errors:
> 
> [tbolsh]$ dmd TestBoxer
> gcc TestBoxer.o -o TestBoxer -m32 -lphobos -lpthread -lm
> TestBoxer.o(.gnu.linkonce.t_D3std5boxer27__T5unboxTC9TestBoxer4TestZ5unboxFS3std5boxer3BoxZC9TestBoxer4Test+0x1a):
> In function
> `_D3std5boxer27__T5unboxTC9TestBoxer4TestZ5unboxFS3std5boxer3BoxZC9TestBoxer4Test':
> TestBoxer.d: undefined reference to `_assert_3std5boxer'

This is a known issue with DMD.  Basically, Phobos is built in release 
mode so these functions are not generated in the std.boxer object file. 
  When you import std.boxer into your app and build with -debug set, the 
template code for std.boxer is built into the app itself, with 
references to the code it thinks is in Phobos (but isn't).

Since DMD always links against phobos.lib regardless of whether the app 
has -debug set, what I do for pure template modules like std.boxer is 
build them with -debug set and link that code into the lib.  This makes 
the assert code and such available if it's needed, and if not it simply 
won't be used.  It's not ideal, but it's a reasonable workaround until 
something is done about this issue.


Sean