Question about LDC and --gc-sections

[H. S. Teoh]

On Friday, 26 October 2018 at 13:03:58 UTC, kinke wrote:
[...]
> What you could try is using an ld version script to override 
> symbol visibility - create a little text file like this:
>
> ---
> CODEABI_1.0 {
>     global: *entry_point*;
>     local: *;
> };
> ---
>
> and then pass it to ld via `ldc2 ... 
> -L--version-script=<path>`. It got the size down to ~900 KB for 
> my dummy .so. Found here: 
> http://anadoxin.org/blog/control-over-symbol-exports-in-gcc.html

Whoa.  That did the trick!

Before: 6.1MB
After: 1.1MB

Not quite the 600KB of the executable, but good enough, in the 
same ballpark.  Now my APK is back down to a sane size (relative 
to its contents)!

Thanks for the tip!!!

P.S. For anyone else interested in this: since I'm mainly calling 
my D code from Java via JNI, I set up the version script to have 
symbols of the form `Java_*` be marked global, and everything 
else local.  Then throw in --gc-sections, and voila, most of the 
redundant symbols are gone.  There are still a few that aren't, 
I'm trying to track down where exactly they're referenced, but 
most of the work has already been done.