llvm dev - Jan 2016 - Why do we static link all llvm libraries in every executable?

Hi 

 

I found basically all llvm libraries are statically linked into each
executable and LLVMgold.so,

This make the clang/llvm package larger and larger with a lot of duplicated
code. If I build

debug version, the disk space required is even larger. Is there any
particular reason to keep 

doing this way? If we separate several shared libraries something like
libclang.so, libllvm.so 

and let all executables and llvmgold.so just linked with .so. A lot of space
could be saved and

loading performance could be improved. 

 

Yin 

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On Mon, Jan 25, 2016 at 10:13:35AM -0800, Yin Ma via llvm-dev
wrote:
> If we separate several shared libraries something like
> libclang.so, libllvm.so and let all executables and llvmgold.so just
> linked with .so. A lot of space could be saved and
> loading performance could be improved. 
There is a build option to do exactly that. It comes at a significant
price for startup, e.g. clang will take 10x as long for building a small
example.

Joerg

On Mon, Jan 25, 2016 at 07:16:20PM +0100, Joerg Sonnenberger via llvm-dev
wrote:
> On Mon, Jan 25, 2016 at 10:13:35AM -0800, Yin Ma via llvm-dev wrote:
> > If we separate several shared libraries something like
> > libclang.so, libllvm.so and let all executables and llvmgold.so just
> > linked with .so. A lot of space could be saved and
> > loading performance could be improved. 
> 
> There is a build option to do exactly that. It comes at a significant
> price for startup, e.g. clang will take 10x as long for building a small
> example.
Namely BUILD_SHARED_LIBS=ON

I find it very useful for dev builds!

On 01/25/2016 09:16 PM, Joerg Sonnenberger via llvm-dev
wrote:
> On Mon, Jan 25, 2016 at 10:13:35AM -0800, Yin Ma via llvm-dev wrote:
>> If we separate several shared libraries something like
>> libclang.so, libllvm.so and let all executables and llvmgold.so just
>> linked with .so. A lot of space could be saved and
>> loading performance could be improved.
>
> There is a build option to do exactly that. It comes at a significant
> price for startup, e.g. clang will take 10x as long for building a small
> example.
Is this to process runtime relocations or run constructors? I wonder if 
Prelink or ElfHack could help.
> Joerg
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