Qt Creator fails to update project when removing static lib

[J0Nes]

Hey Qt community!
I am having a Qt subproject that is linking against a static library (boost filesystem) like so:

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../3rdParty/boost/lib/win/ -llibboost_filesystem-vc141-mt-x64-1_72
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../3rdParty/boost/lib/win/ -llibboost_filesystem-vc141-mt-gd-x64-1_72
else:unix: LIBS += -L$$PWD/../3rdParty/boost/lib/macos/ -lboost_filesystem

INCLUDEPATH += $$PWD/../3rdParty/boost/include
DEPENDPATH += $$PWD/../3rdParty/boost/include

win32:!win32-g++:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../3rdParty/boost/lib/win/libboost_filesystem-vc141-mt-x64-1_72.lib
else:win32:!win32-g++:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../3rdParty/boost/lib/win/libboost_filesystem-vc141-mt-gd-x64-1_72.lib
else:unix: PRE_TARGETDEPS += $$PWD/../3rdParty/boost/lib/macos/libboost_filesystem.a

When I remove the static library (so the entire block) from the .pro file of my subproject I do get an error when building:

:-1: error: LNK1104: cannot open file 'libboost_filesystem-vc141-mt-gd-x64-1_72.lib'

I tried all kinds of things like restarting Qt Creator, rebuilding, cleaning, deleting the shadow build directory. Nothing seems to work. I really don't understand why Qt Creator continues to look for the .lib.
Is there any cache I am missing?

My selected Kit is MSVC 2017 15.9 (amd64), Qt 5.13.0 MSVC2017 (64 bit)

Thanks for your help!

[aha_1980]

Hi @J0Nes,

please check if you have a stale Makefile laying around.

Regards

[J0Nes]

Hey,

nope, the only makefile is in the shadowbuild directory which I explicitly delete

[J0Nes]

Turns out that just including boost/process.hpp auto links against the mentioned library. I was not aware that this is even possible.
Thanks for your help