Large DSO created for qmlextensionplugins - 1.5MB vs 28KB

[shrkamat]

QML extension plugins need not link with Widgets library, is there a work around to avoid this ?

Dynamic section at offset 0x172c88 contains 37 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libstdc++.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libQt5Widgets.so.5]
 0x0000000000000001 (NEEDED)             Shared library: [libQt5Gui.so.5]
 0x0000000000000001 (NEEDED)             Shared library: [libQt5Core.so.5]
 0x0000000000000001 (NEEDED)             Shared library: [libQt5Quick.so.5]
 0x0000000000000001 (NEEDED)             Shared library: [libQt5Qml.so.5]
 0x0000000000000001 (NEEDED)             Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [librt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [ld-linux-x86-64.so.2]

stripped plugin DSO size by rust - 1.5MB. Is it because of the rust runtime ?

   text	   data	    bss	    dec	    hex	filename
1482252	  60274	   1208	1543734	 178e36	target/release/libih.so

stripped plugin DSO size by Qt - 28KB

   text	   data	    bss	    dec	    hex	filename
  21589	   1960	     72	  23621	   5c45	libqmlqtimeexampleplugin.so

[ogoffart]

One can try to remove this line and see if it works:

https://github.com/woboq/qmetaobject-rs/blob/master/qmetaobject/build.rs#L83

But I think we need Widgets so the Quick Control works.

We could imagine a cargo feature to enable/disable widgets.

[ratijas]

I think, the global issue here is to feature-flag all (or at least, most of) Qt modules, in a manner of winapi-rs. Then each set of wrappers would have to be either opted-in or could be opted-out, depending on how do go about defaults.

I mean, check it out all those features and their huge map of dependencies in Cargo.toml and build.rs! https://github.com/retep998/winapi-rs/blob/0.3/build.rs