Problem with qmake generated makefile name in subdirectories for Qt 5.6

[Ramakanth]

Using the below command in makefile to generate the makefile for top and sub directories with name Makefile_g.
The top level directory generates the makefile with name "Makefile_g" but subdirectories makefiles are generated with "Makefile" in Qt5.6. Incase of Qt 4.8, both the top directory and subdirectories makefiles are generated with "Makefile_g" filename.

Makefile_g: $(PRO_FILE_NAME)
$(QMAKEPATH)qmake -o $@ $(QMAKESPEC_SWITCH) $(QMAKESPEC) $<

Here $(PRO_FILE_NAME) is top level pro file.
QMAKEPATH incase of ubuntu is /usr/local/Qt-5.6.3/bin and $(QMAKESPEC_SWITCH) $(QMAKESPEC) are empty incase of ubuntu.

Donot see any qmake option difference between Qt 4.8 and Qt 5.6 https://doc.qt.io/qt-5/qmake-running.​html.

qmake --version
QMake version 3.0
Using Qt version 5.6.3 in /usr/local/Qt-5.6.3/lib

Is this a known issue in qmake generator make file code in Qt 5.6(qmake/generators/makefile.cpp)?
Any suggestions are appreciated.

[SGaist]

Hi,

Can you provide a minimal compilable example project that shows that issue ?

[Ramakanth]

@SGaist
Attached is the minimal compilable example project showing the issue.
Incase unable to view the example, attached the same project in https://bugreports.qt.io/browse/QTBUG-87742

Ensure Qt 5.6.3 is installed in the path /usr/local/Qt-5.6.3.
The top level handwritten makefile uses TestQmake.pro to generate Makefile_g in the current directory but not in sub-directory unlike Qt 4.8.

Makefile_g: $(PRO_FILE_NAME)
$(QMAKEPATH)qmake -o $@ $(QMAKESPEC_SWITCH) $(QMAKESPEC) $<

To build the example project:
cd TestQmake
make clean
make all

Expected: The makefile in subdirectory testwidget should be generated with filename "Makefile_g"
Actual: The makefile in subdirectory testwidget is generated with filename "Makefile"