Thread overview
dmd verus ldmd2 -lib option
Feb 01, 2014
Dan Olson
Feb 03, 2014
Kai Nacke
Feb 05, 2014
Dan Olson
February 01, 2014
I noticed that dmd -lib breaks up a module into separate .o's when building a static library.  This is could help make smaller executables (I am thinking smart phones) when linking with phobos because it will only pull in to .o's needed to satisfy what is referenced.

ldmd2 -lib doesn't split into multiple .o's like dmd.  Does it seem like a good idea to do the same (I am thinking so).

Example: file testlib.d gets split into four .o's
cat >testlib.d <<eof
void foo() {}
void bar() {}
void xyzzy() {}
eof
$ dmd -lib -oflibtest.a testlib.d
$ nm libtest.a

libtest.a(testlib.o):
0000000000000050 D _D7testlib12__ModuleInfoZ
0000000000000030 T _D7testlib15__unittest_failFiZv
0000000000000000 T _D7testlib7__arrayZ
0000000000000018 T _D7testlib8__assertFiZv
                 U __d_array_bounds
                 U __d_assertm
                 U __d_unittestm

libtest.a(testlib_1_144.o):
0000000000000000 S _D7testlib3fooFZv

libtest.a(testlib_2_135.o):
0000000000000000 S _D7testlib3barFZv

libtest.a(testlib_3_25e.o):
0000000000000000 S _D7testlib5xyzzyFZv
February 03, 2014
On Saturday, 1 February 2014 at 23:51:06 UTC, Dan Olson wrote:
> I noticed that dmd -lib breaks up a module into separate .o's when
> building a static library.  This is could help make smaller executables
> (I am thinking smart phones) when linking with phobos because it will
> only pull in to .o's needed to satisfy what is referenced.
>
> ldmd2 -lib doesn't split into multiple .o's like dmd.  Does it seem like
> a good idea to do the same (I am thinking so).
>
> Example: file testlib.d gets split into four .o's
> cat >testlib.d <<eof
> void foo() {}
> void bar() {}
> void xyzzy() {}
> eof
> $ dmd -lib -oflibtest.a testlib.d
> $ nm libtest.a
>
> libtest.a(testlib.o):
> 0000000000000050 D _D7testlib12__ModuleInfoZ
> 0000000000000030 T _D7testlib15__unittest_failFiZv
> 0000000000000000 T _D7testlib7__arrayZ
> 0000000000000018 T _D7testlib8__assertFiZv
>                  U __d_array_bounds
>                  U __d_assertm
>                  U __d_unittestm
>
> libtest.a(testlib_1_144.o):
> 0000000000000000 S _D7testlib3fooFZv
>
> libtest.a(testlib_2_135.o):
> 0000000000000000 S _D7testlib3barFZv
>
> libtest.a(testlib_3_25e.o):
> 0000000000000000 S _D7testlib5xyzzyFZv

Hi Dan,

that's a in ldmd2. Could you please create an issue?
https://github.com/ldc-developers/ldc/issues?state=open

Thanks!!!

Regards,
Kai
February 05, 2014
https://github.com/ldc-developers/ldc/issues/579