--- openal-soft-1.16.0/CMakeLists.txt.orig	2015-02-04 16:45:20.927176000 +0100
+++ openal-soft-1.16.0/CMakeLists.txt	2015-02-04 16:45:50.209103900 +0100
@@ -479,7 +479,10 @@
 ENDIF()
 
 # Check if we have Windows headers
+IF(WIN32 AND NOT CYGWIN)
 CHECK_INCLUDE_FILE(windows.h HAVE_WINDOWS_H -D_WIN32_WINNT=0x0502)
+ENDIF(WIN32 AND NOT CYGWIN)
+
 IF(NOT HAVE_WINDOWS_H)
     CHECK_FUNCTION_EXISTS(gettimeofday HAVE_GETTIMEOFDAY)
     IF(NOT HAVE_GETTIMEOFDAY)