Make: missed separator in implicit rules definition

Question

I install Eric IDE on Windows 7, and it requires QScintilla2 library. I tried to build that library using qmake and MinGW's make and got a make error:

make -f Makefile.Release
make[1]: Entering directory `/d/Install/QScintilla-gpl-2.7.2/Qt4Qt5'
Makefile.Release:481: *** missing separator.  Stop.
make[1]: Leaving directory `/d/Install/QScintilla-gpl-2.7.2/Qt4Qt5'
make: *** [release] Error 2

Makefile content:

####### Implicit rules

.SUFFIXES: .c .cpp .cc .cxx

{..\lexlib}.cpp{release\}.obj:: ## line 481
    $(CXX) -c $(CXXFLAGS) $(INCPATH) -Forelease\ @<<
    $<
<<

I'm not familiar with make, so could anyone explain what does this code mean and how to fix the error?

NOTE: when I insert \t before <<, I got the following error:

make[1]: *** [{..\lexlib}.cpp{release\}.obj] Error 2
make[1]: Leaving directory `/d/Install/QScintilla-gpl-2.7.2/Qt4Qt5'
make: *** [release] Error 2