Created attachment 101173 [details]
example project

I have a project with a custom qmake based build (I can't use qmake build but need the custom build system for some reason not important here). The build is done in a separate build directory and has a subproject (see attached example).

The project layout is as follows:

/home/fifr/test/test_project/test_project.pro
/home/fifr/test/test_project/sub_project/sub_project.pro
/home/fifr/test/test_project/sub_project/hello.c

The build directory is

/home/fifr/test/test_project_build

The only custom build option is "compile" with calling "qmake ../test_project".

If there is some bug in hello.c, the compile output looks as follows

/home/fifr/test/test_project_build> make 
cd sub_project/ && ( test -e Makefile || /usr/lib/qt/bin/qmake /home/fifr/test/test_project/sub_project/sub_project.pro -o Makefile ) && /usr/bin/make -f Makefile 
make[1]: Verzeichnis „/home/fifr/test/test_project_build/sub_project“ wird betreten
gcc -c -pipe -O2 -march=x86-64 -mtune=generic -O2 -pipe -fstack-protector-strong -Wall -W -D_REENTRANT -fPIC -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I../../test_project/sub_project -I. -isystem /usr/include/qt -isystem /usr/include/qt/QtGui -isystem /usr/include/qt/QtCore -I. -I/usr/lib/qt/mkspecs/linux-g++ -o hello.o ../../test_project/sub_project/hello.c
../../test_project/sub_project/hello.c: In Funktion »main«:
../../test_project/sub_project/hello.c:4:5: Fehler: »i« nicht deklariert (erste Benutzung in dieser Funktion)
     i=0;
     ^
../../test_project/sub_project/hello.c:4:5: Anmerkung: jeder nicht deklarierte Bezeichner wird nur einmal für jede Funktion, in der er vorkommt, gemeldet

The problemt is that clicking on the error message "../../test_project/sub_project/hello.c:4:5: ..." opens the file "/home/fifr/test_project/sub_project/hello.c" (note the missing "test/" in the path). It seems as if the path to file "hello.c" is taken relative to the build directory "test_project_build" instead to its subdirectory "test_project_build/sub_project", which would be correct (but this is only a rough guess).