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digitalmars.D.ldc - WebAssembly template size bold and export un wanted symbol!

reply learnfirst1 <learnfirst1 gmail.com> writes:
I try to build WebAssembly project, the wasm size is grow into 
300kb even with "-Os -inline -release -noboundscheck".


there is a lot symbol like:

_foreachbody2MFPSQDfQDd10GameAssertZQBnMFPSQEfQEd10GameMethodZQCnMFPSQFfQFd12S2OptionZi


To build a c base game engine the size only like 90kb,  to build 
with D there is not so much login the size already be huge.


And the LLD is not inline  function for WASM like linux static 
binary format.

How can we cut down the size so we can make the LDC  generate 
WASM more deploy friendly.


Hidden un want symbol can cut down the size huge,  since WASM 
really don't want to expose internal symbol.   I think some 
option like https://github.com/ldc-developers/ldc/issues/2431  
will be great.

Please share your opinion.
Aug 09 2018
parent Radu <void null.pt> writes:
On Friday, 10 August 2018 at 06:41:51 UTC, learnfirst1 wrote:

 I try to build WebAssembly project, the wasm size is grow into 
 300kb even with "-Os -inline -release -noboundscheck".


 there is a lot symbol like:

 _foreachbody2MFPSQDfQDd10GameAssertZQBnMFPSQEfQEd10GameMethodZQCnMFPSQFfQFd12S2OptionZi


 To build a c base game engine the size only like 90kb,  to 
 build with D there is not so much login the size already be 
 huge.


 And the LLD is not inline  function for WASM like linux static 
 binary format.

 How can we cut down the size so we can make the LDC  generate 
 WASM more deploy friendly.


 Hidden un want symbol can cut down the size huge,  since WASM 
 really don't want to expose internal symbol.   I think some 
 option like https://github.com/ldc-developers/ldc/issues/2431  
 will be great.

 Please share your opinion.


Indeed there will be dead code left in the binary. This example 
shows that the foreach body gets inlined but the symbol emitted 
is still present.

https://godbolt.org/g/hwU8Zf

I think this will get solved by newer LLD (LLVM linker), I see 
that they added a `-gc-sections` option. 
https://github.com/llvm-mirror/lld/blob/master/wasm/Options.td#L70
Aug 10 2018