I can't add an icon to the executable in qt - c++

Question

I can't seem to add an icon to the exe file in QT. I already added it to the top left corner but when I add RC_FILES = icon.ico to my .pro file it gives me an error in the generated resource file. The error says myapp_resource_res.o Error 1. This is my .pro file:
#-------------------------------------------------
#
# Project created by QtCreator 2017-07-18T13:42:18
#
#-------------------------------------------------
QT += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = MentalMath3
TEMPLATE = app
# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS
# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain
version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the
APIs deprecated before Qt 6.0.0
SOURCES += \
main.cpp \
mainwindow.cpp
HEADERS += \
mainwindow.h
FORMS += \
mainwindow.ui
RC_ICONS = icon.ico
This is the generated resource.o file:
#include <windows.h>
IDI_ICON1 ICON DISCARDABLE "C:\\Users\\abhi\\Desktop\\Mental
Math\\MentalMath3\\icon.ico"
VS_VERSION_INFO VERSIONINFO
FILEVERSION 0,0,0,0
PRODUCTVERSION 0,0,0,0
FILEFLAGSMASK 0x3fL
#ifdef _DEBUG
FILEFLAGS VS_FF_DEBUG
#else
FILEFLAGS 0x0L
#endif
FILEOS VOS__WINDOWS32
FILETYPE VFT_DLL
FILESUBTYPE 0x0L
BEGIN
BLOCK "StringFileInfo"
BEGIN
BLOCK "040904b0"
BEGIN
VALUE "CompanyName", "\0"
VALUE "FileDescription", "\0"
VALUE "FileVersion", "0.0.0.0\0"
VALUE "LegalCopyright", "\0"
VALUE "OriginalFilename", "MentalMath3.exe\0"
VALUE "ProductName", "MentalMath3\0"
VALUE "ProductVersion", "0.0.0.0\0"
END
END
BLOCK "VarFileInfo"
BEGIN
VALUE "Translation", 0x0409, 1200
END
END
/* End of Version info */

Answer 1

i had the same problem when am developing my qt application, to solve the problem.
first step :
create a resource file named like your project for example my project is Qtapp so the resource file will be "Qtapp.rc" inside of it :
#include <windows.h>
IDI_ICON1 ICON DISCARDABLE "iconEXE.ico"
second step:
return in you .pro file and add the resource file like this
RC_FILE = Qtapp.rc
and enjoye