Windows - Linker fails because main.obj not found. Where are my compiled .obj files?

Sebastian_-_-_

It seems like my files compile fine, but when I finally get to linking stage it can't find them. They aren't there when I look in the configured build directory, although moc_(...).cpp files are in there.

This is an example of the cl command that qt is using:

cl -c -nologo -Zc:wchar_t -FS -Zc:rvalueCast -Zc:inline -Zc:strictStrings -Zc:throwingNew -Zc:referenceBinding -Zc:__cplusplus -P -O2 -MD -std:c++17 -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -wd4467 -EHsc -DUNICODE -D_UNICODE -DWIN32 -D_ENABLE_EXTENDED_ALIGNED_STORAGE -DWIN64 -DQT_NO_DEBUG -DQT_CHARTS_LIB -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DNDEBUG -I..\rdk_qt -I. -I..\..\rdk_qt_common\rdk_qt_common -I..\..\..\..\Downloads\vcpkg\installed\x64-windows\include -I..\..\rdk\include -I..\..\rdk_core\include -I..\..\generic_multi_map -I..\generated -I..\..\rdk\win_build_dep\boost -I..\..\rdk\win_build_dep\yaml-cpp\include -IC:\Qt\5.12.6\msvc2017_64\include -IC:\Qt\5.12.6\msvc2017_64\include\QtCharts -IC:\Qt\5.12.6\msvc2017_64\include\QtWidgets -IC:\Qt\5.12.6\msvc2017_64\include\QtGui -IC:\Qt\5.12.6\msvc2017_64\include\QtANGLE -IC:\Qt\5.12.6\msvc2017_64\include\QtNetwork -IC:\Qt\5.12.6\msvc2017_64\include\QtCore -Irelease -I/include -IC:\Qt\5.12.6\msvc2017_64\mkspecs\win32-msvc -Forelease\ @C:\Users\sebas\AppData\Local\Temp\nm519B.tmp
main.cpp
show_dialog.cpp
transform_manager.cpp

I am wondering if the -Forelease\ @C:\Users\sebas\AppData\Local\Temp\nm519B.tmp option could be the issue. Why is there \ @ in the path? I understand that this option sets the output location for the .obj files, but shouldn't that be the configured build directory? What is this .tmp folder?

Later on I get the linker error which prevents my build:

link /NOLOGO /DYNAMICBASE /NXCOMPAT /INCREMENTAL:NO /SUBSYSTEM:CONSOLE "/MANIFESTDEPENDENCY:type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' publicKeyToken='6595b64144ccf1df' language='*' processorArchitecture='*'" /MANIFEST:embed /OUT:release\RDK.exe @C:\Users\sebas\AppData\Local\Temp\nm9C2D.tmp
LINK : fatal error LNK1181: cannot open input file 'release\main.obj'

I'm porting this project from linux and I'm a bit new to windows, so any help is appreciated. I'm trying to manually run the cl commands and see if I generates an .obj file for me. But even if that works I still need to get this working in the normal way.

OS: Windows 10
QT-Creator: 4.10.2
QT: 5.13.2
MSVC: 2017, 32 bit

JonB

@Sebastian_-- said in Windows - Linker fails because main.obj not found. Where are my compiled .obj files?:

-Forelease\ @C:\Users\sebas\AppData\Local\Temp\nm519B.tmp

Hello and welcome.

The @C:\Users\sebas\AppData\Local\Temp\nm519B.tmp is a MSVC link response file. The @ means that it reads the content of that file for linker input/options. It is often used because of restrictions on Windows/LINK command-line length. Doubtless the build process puts the LINK input files into that temporary file when it is about to call LINK. You probably won't be able to find the file after the linking has finished as it will deleted.

I think the -Forelease\ is its own option, not joined to the @C:\... which comes after it. So your "output" directory is named release. It's a relative path, so presumably relative to wherever the command is running.

LINK : fatal error LNK1181: cannot open input file 'release\main.obj'

Go find where this file is actually located. If necessary search your whole disk(s) for main.obj and see what it comes up with.

Sebastian_-_-_

Hello and thanks for the response. I am glad to learn from your explanation.

My issue was caused by my stupid mistake. I was using the -P compiler flag as suggested online to help debug something else. I didn't realize that this would suppress the compilation and generation of .obj files. So I left it on and this was causing my issue.

Thanks again for your help.

JonB

@Sebastian_-- said in Windows - Linker fails because main.obj not found. Where are my compiled .obj files?:

I didn't realize that this would suppress the compilation and generation of .obj files.

:)