Trouble compiling Wine tests with Cygwin

[Alex Villací­s Lasso]

I have a VB6 application that requires oledb32 to convert from 
DBTYPE_VARIANT to DBTYPE_BYTES, and fails with builtin oledb32 since 
conversions to DBTYPE_BYTES are unimplemented. I set up a VirtualBox VM 
with Windows XP and the latest Cygwin in order to add a oledb32 test to 
show me what should be done for these conversions to DBTYPE_BYTES. 
However, I have trouble when running "make test" on dlls/oledb32/tests. 
I get the following:

../../../tools/winegcc/winegcc  -B../../../tools/winebuild 
--sysroot=../../..  convert.o marshal.o   convert_i.o   testlist.o -o 
oledb32_test.exe ../../../libs/port/libwine_port.a -loleaut32 -lole32 
-luser32 -lgdi32 -ladvapi32 -lkernel32
oledb32_test.BkIKxE.s: Assembler messages:
oledb32_test.BkIKxE.s:5: Error: junk at end of line, first unrecognized 
character is `"'
oledb32_test.BkIKxE.s:14: Error: unknown pseudo-op: `.hidden'
oledb32_test.BkIKxE.s:69: Error: unknown pseudo-op: `.hidden'
oledb32_test.BkIKxE.s:74: Error: junk at end of line, first unrecognized 
character is `"'
oledb32_test.BkIKxE.s:76: Error: junk at end of line, first unrecognized 
character is `-'
winebuild: /usr/bin/as.exe failed with status 256
winegcc: ../../../tools/winebuild/winebuild.exe failed
make: *** [oledb32_test.exe] Error 2

This is the version of as that comes with the latest cygwin:

GNU assembler (GNU Binutils) 2.19.51.20090704
Copyright 2008 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or later.
This program has absolutely no warranty.
This assembler was configured for a target of `i686-cygwin'.

I have searched in www.winehq.org but could not find anything relevant 
on my problem. I have also tried to save the assembler file by using 
-Wb,--save-temps but I cannot make it work.