msgpack link failure - non-transitive pragma(lib)?

[Basile B.]

On Friday, 11 May 2018 at 12:35:52 UTC, TED_996 wrote:
> I've been trying to debug this for a long time now. I am trying 
> to build one of the msgpack examples 
> (examples/upacker_foreach.d) and the linking failed. I have 
> since succeeded and I'm trying to find out if this is intended 
> behavior or a bug in D (not msgpack, I think).
>
> TL;DR: it seems to me like the pragma(lib, "ws2_32"); in 
> core.sys.windows.winsock2, imported in msgpack.common, imported 
> in msgpack (package.d), imported in my source files, does not 
> hold; this was fixed when I added the pragma in my source file 
> too.
>
> Versions: Windows 10, dmd 2.080.0, dub 1.9.0
>
> The dub build output:
>
> Performing "debug" build using D:\D\dmd2\windows\bin\dmd.exe 
> for x86.
> msgpack-d 1.0.0-beta.6: target for configuration "library" is 
> up to date.
> hw ~master: building configuration "application"...
> Linking...
>
> OPTLINK (R) for Win32  Release 8.00.17
> Copyright (C) Digital Mars 1989-2013  All rights reserved.
> http://www.digitalmars.com/ctg/optlink.html
> .dub\build\application-debug-windows-x86-dmd_2080-1E3111031ACEC4AEF53C62127331208A\hw.obj(hw)
>  Error 42: Symbol Undefined _ntohl at 4
> .dub\build\application-debug-windows-x86-dmd_2080-1E3111031ACEC4AEF53C62127331208A\hw.obj(hw)
>  Error 42: Symbol Undefined _ntohs at 4
> Error: linker exited with status 2
> D:\D\dmd2\windows\bin\dmd.exe failed with exit code 1.
>
> dub.json:
>
> {
> 	"name": "hw",
> 	"authors": [
> 		"ted_996"
> 	],
> 	"description": "A minimal D application.",
> 	"copyright": "Copyright © 2018, ted_996",
> 	"license": "proprietary",
> 	"dependencies": {
> 		"msgpack-d": ">=1.0.0-beta.6"
> 	}
> }
>
> After some digging, I found that other binaries that used 
> msgpack (DCD) were importing ws2_32, but it seemed like my 
> binary was not. Both debug and release and x86 and x64 versions 
> were failing to link; msgpack built fine but probably only the 
> msgpack.lib file (no final link).
>
> However, when I (counter-intuitively, for me) added pragma(lib, 
> "ws2_32"); to my own source files, it built successfully. 
> Should that have been necessary? it was not in any examples. 
> What gives?
>
> Thanks!

Yeah, right guess in the title ;)
you have to put the "pragma lib" again. Take the use of "pragma 
lib" in the binding as an information saying "you have to do this 
too".