How to link 3rd party libraries?

Vadi2

I'm getting this at the end of my compile:

shared:WARNING: emcc: cannot find library "lua5.1"
shared:WARNING: emcc: cannot find library "hunspell"
shared:WARNING: emcc: cannot find library "pcre"
shared:WARNING: emcc: cannot find library "zip"
shared:WARNING: emcc: cannot find library "z"
shared:WARNING: emcc: cannot find library "pugixml"
error: Linking globals named 'regerror': symbol multiply defined!
shared:WARNING: Note: Input file "@/tmp/tmpfsjXvo.response" did not exist.
shared:ERROR: Failed to run llvm optimizations: 
Makefile:1354: recipe for target 'mudlet.js' failed
make: *** [mudlet.js] Error 1

Emscripten has documentation on it here, but... how does that related to Qt? Qt docs also don't mention 3rd party libraries, so it's not entirely clear on what to do :(

lorn.potter

They need to be static libraries, as shared libraries are not yet supported in Qt WebAssembly.

Vadi2

Thanks! I have no experience building static libraries, any tips on how to get started?

If I understand correctly, I can just build the library statically with my Qt application - I don't have to build Qt statically as well?

Vadi2

@lorn-potter any tips on how to do this? It's rather common for any real application to require more than just Qt.

Pradeep P N

@Vadi2 Did you build the libraries or just downloaded and used them directly ?

Vadi2

On Windows we build them, on Ubuntu we install the -dev packages, on macOS we use Homebrew.

Vadi2

Any insights in this area would be appreciated! Any application big enough is bound to have dependencies.

lorn.potter

@Vadi2

Other than adding your libs with LIBS += -lblahblah
you shouldn't have to pass anything extra to Qt to get it to link statically, as QtWebAssembly does that anyway.

You could try QMAKE_LFLAGS += -static in your project if there is any issues, or it tries to link dynamically.