DUB and Gtk-d reduce size of huge executable, build dynamic dependencies

[Gerald]

On Wednesday, 7 March 2018 at 10:51:49 UTC, CSim wrote:
> Hi,
>
> I'm trying to decide whether it is better to use DLang for Gtk 
> development or Vala/Genie.
>
> When I make a simple Vala/Genie Gtk executable the file is tiny 
> whereas the DLang file is huge.  First I used the default Dub 
> build and the file was in excess of 60mb (assuming this 
> includes debug build).  Using dub build=release the file is 
> still more than 7 mb.  Using a native Vala/Genie build the file 
> is less than 500k.
>
> Trying to understand what is going on, but I assume from this 
> that Dub is linking static dependencies, whereas the Vala/Genie 
> builds will link to dynamic libraries.
>
>
> So my (two pronged) question is this:  Is there any way to 
> specify in dub.json to build and link dependencies as dynamic 
> libraries, and are there any other tips that can be used to 
> reduce these (relatively) huge executables?

Personally, I do not worry too much about the executable size, 
however a couple of tips as follows:

a. If this is on linux use "strip" to remove symbols out of the 
executable

b. In dub.json you can specify just the portions of GtkD that 
your application depends on, i.e.:

     "dependencies": {
         "gtk-d:gtkd": {
             "version": "3.7.5"
         },
         "gtk-d:vte": {
             "version": "3.7.5"
         }
     }

Is what I use in tilix (https://github.com/gnunn1/tilix)

c. You can dynamically link to GtkD, in tilix I have the config 
below to do so. Interestingly on ldc it doesn't make any 
difference in size though using ldd I can see the dependency to 
GtkD. With DMD it is smaller however I cannpt run it since the 
Arch Linux GtkD package is compiled with ldc2.

         {
             "name": "dynamic",
             "targetType": "executable",
             "libs": ["gtkd-3"],
             "libs-linux": ["X11"],
             "lflags": ["-defaultlib=libgtkd-3.so"],
             "versions": ["StdLoggerDisableTrace"]
         }