diff --git a/configure/os/CONFIG.Common.win32-x86-mingw b/configure/os/CONFIG.Common.win32-x86-mingw
index 5727bf486..cdbe3e2e1 100644
--- a/configure/os/CONFIG.Common.win32-x86-mingw
+++ b/configure/os/CONFIG.Common.win32-x86-mingw
@@ -12,6 +12,7 @@ include $(CONFIG)/os/CONFIG.Common.UnixCommon
 
 OS_CLASS = WIN32
 ARCH_CLASS = x86
+POSIX = NO
 
 #  Definitions used when COMMANDLINE_LIBRARY is READLINE
 LDLIBS_READLINE = -lreadline -lcurses