SIP install fails (make install): "cannot find file"

Question

Trying to get PyQt 5.3.2 installed, I have so far installed Qt and SIP.

(Running Windows 7, Python 3.4, SIP 4.16.4, Qt 5, Gnu make 3.8.1).

Below is the text from the DOS window:

C:\sip-4.16.4>python configure.py --platform win32-g++
This is SIP 4.16.4 for Python 3.4.2 on win32.
The SIP code generator will be installed in C:\Python34.
The sip module will be installed in C:\Python34\Lib\site-packages.
The sip.h header file will be installed in C:\Python34\include.
The default directory to install .sip files in is C:\Python34\sip.
Creating siplib\sip.h...
Creating siplib\siplib.c...
Creating siplib\siplib.sbf...
Creating sipconfig.py...
Creating top level Makefile...
Creating sip code generator Makefile...
Creating sip module Makefile...

C:\sip-4.16.4>"C:\Program Files (x86)\GnuWin32\bin\make" install
make[1]: Entering directory `C:/sip-4.16.4/sipgen'
makefile:29: warning: overriding commands for target `.c.o'
makefile:26: warning: ignoring old commands for target `.c.o'
gcc -c -O2 -w -DNDEBUG -DUNICODE -DQT_LARGEFILE_SUPPORT -I. -o main.o main.c
process_begin: CreateProcess(NULL, gcc -c -O2 -w -DNDEBUG -DUNICODE -DQT_LARGEFI
LE_SUPPORT -I. -o main.o main.c, ...) failed.
make (e=2): The system cannot find the file specified.
make[1]: *** [main.o] Error 2
make[1]: Leaving directory `C:/sip-4.16.4/sipgen'
make: *** [install] Error 2

It is not clear what file is missing... it seems to be "main.o", but Makefile does not name such file - see below:

all:
        @$(MAKE) -C sipgen
        @$(MAKE) -C siplib

install:
        @$(MAKE) -C sipgen install
        @$(MAKE) -C siplib install
        @if not exist C:\Python34\Lib\site-packages mkdir C:\Python34\Lib\site-packages
        copy /y sipconfig.py C:\Python34\Lib\site-packages\sipconfig.py
        copy /y C:\sip-4.16.4\sipdistutils.py C:\Python34\Lib\site-packages\sipdistutils.py

clean:
        @$(MAKE) -C sipgen clean
        @$(MAKE) -C siplib clean

I have spent oodles of hours to get to this point, and have done many, many searches. When I find something similar to this, the thread dies without a resolution. Note that my Unix/Linux background is close to non-existent, so I expect this to be a trivial error. Could be related to the two makefile warnings (#29, #26)...?

Thanks in advance for any comment.