Question about LDC and --gc-sections

[kinke]

On Thursday, 25 October 2018 at 17:19:05 UTC, H. S. Teoh wrote:
> I suspect it may be because the target is an .so rather than an 
> executable, so the linker may be leaving in all public symbols 
> as a precaution.

Seems like it. The size of a std.stdio hello-world executable 
with static druntime/Phobos on Linux x64 is about 900 KB, as 
shared lib it's > 6 MB.

> How do I tell the linker (clang) to drop everything except the 
> small handful of entry points required by the Android API?

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