Link library whole archive doesn't work with CMake Ninja generator

[ahayzen]

If you use -G Ninja then it doesn't understand the WHOLE_ARCHIVE workaround ? Is there a way to make this work with Ninja too (seems some use --whole-archive?) or do we need to look for an alternate route to WHOLE_ARCHIVE ?

[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-features-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-minimal-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,cxx-qt-demo-threading-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-features-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-minimal-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,cxx-qt-demo-threading-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-features-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,qml-minimal-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 
[cmake] 
[cmake] CMake Error:
[cmake]   Error evaluating generator expression:
[cmake] 
[cmake]     $<LINK_LIBRARY:WHOLE_ARCHIVE,cxx-qt-demo-threading-static>
[cmake] 
[cmake]   Expression did not evaluate to a known generator expression
[cmake] 

[Be-ing]

I use the Ninja generator. What version of CMake are you using? The LINK_LIBRARY generator expression was added in CMake 3.24.

[ahayzen-kdab]

This is with CMake from Ubuntu 22.04, curious that CI doesn't fail, i guess github are installing a new CMake from somewhere.

$ cmake --version
cmake version 3.22.1

So it looks like we either need to

• Use target_link_options(${APP_NAME}_lib INTERFACE "SHELL:-Wl,--whole-archive $<TARGET_FILE:${CRATE}-static> -Wl,--no-whole-archive") instead of "$<LINK_LIBRARY:WHOLE_ARCHIVE,${CRATE}-static>" as described in WASM Example #414
• Bump the CMake minimum version to 3.24 in the CMakeLists.txt

Note that the Qt online installer has 3.24 so developers can use that to retrieve the newer version.

[ahayzen-kdab]

Although as detailed in the wasm issue a newer CMake doesn't work with the wasm target only x86_64. Wonder if this is due to the platforms that the CMake docs say are supported. Also note that it doesn't list MinGW ?

Are there any other alternate ways of solving this? 🤔

[Be-ing]

Use target_link_options(${APP_NAME}_lib INTERFACE "SHELL:-Wl,--whole-archive $<TARGET_FILE:${CRATE}-static> -Wl,--no-whole-archive")

That would require platform-specific code for Unix and Windows. :/

Bump the CMake minimum version to 3.24 in the CMakeLists.txt

I'd prefer to do this.

Although as detailed in the wasm issue a newer CMake doesn't work with the wasm target

Yeah, this seems to be a limitation in CMake currently. But it seems the platform linker does support it, just not CMake.

[ahayzen-kdab]

Use target_link_options(${APP_NAME}_lib INTERFACE "SHELL:-Wl,--whole-archive Unable to render expression.

    $<TARGET_FILE:${CRATE}-static> -Wl,--no-whole-archive")

That would require platform-specific code for Unix and Windows. :/

Bump the CMake minimum version to 3.24 in the CMakeLists.txt

I'd prefer to do this.

Let's do this for now.

Although as detailed in the wasm issue a newer CMake doesn't work with the wasm target

Yeah, this seems to be a limitation in CMake currently. But it seems the platform linker does support it, just not CMake.

And can we if (wasm) then use manual linkers else WHOLE_ARCHIVE thing when/if we add wasm support until upstream CMake fixes it ? Eg can we determine that we are building a CMake target for wasm later ?

[ahayzen-kdab]

Fixed in #445 wasm discussions can be in the other issue