---
 config/gcc-plugin.m4 |   18 +++++++++++++-----
 gcc/configure        |   22 +++++++++++++++-------
 libcc1/configure     |   22 +++++++++++++++-------
 3 files changed, 43 insertions(+), 19 deletions(-)

--- a/config/gcc-plugin.m4
+++ b/config/gcc-plugin.m4
@@ -21,6 +21,9 @@ AC_DEFUN([GCC_ENABLE_PLUGINS],
    pluginlibs=
    plugin_check=yes
 
+   PICFLAG="-fPIC"
+   UNDEFINEDPREAMBLE="extern int X;"
+   UNDEFINEDCODE="return X == 0;"
    case "${host}" in
      *-*-mingw*)
        # Since plugin support under MinGW is not as straightforward as on
@@ -43,6 +46,11 @@ AC_DEFUN([GCC_ENABLE_PLUGINS],
 	 export_sym_check=
        fi
      ;;
+     *-*-mingw*|*-*-cygwin*|*-*-msys*)
+       PICFLAG=""
+       UNDEFINEDPREAMBLE=""
+       UNDEFINEDCODE=""
+     ;;
      *)
        if test x$build = x$host; then
 	 export_sym_check="objdump${exeext} -T"
@@ -94,17 +102,17 @@ AC_DEFUN([GCC_ENABLE_PLUGINS],
      case "${host}" in
        *-*-darwin*)
 	 CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g`
-	 CFLAGS="$CFLAGS -fPIC"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
 	 LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup"
        ;;
        *)
-	 CFLAGS="$CFLAGS -fPIC"
-	 LDFLAGS="$LDFLAGS -fPIC -shared"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
+	 LDFLAGS="$LDFLAGS ${PICFLAG} -shared"
        ;;
      esac
-     AC_MSG_CHECKING([for -fPIC -shared])
+     AC_MSG_CHECKING([for ${PICFLAG} -shared])
      AC_TRY_LINK(
-       [extern int X;],[return X == 0;],
+       [${UNDEFINEDPREAMBLE}],[${UNDEFINEDCODE}],
        [AC_MSG_RESULT([yes]); have_pic_shared=yes],
        [AC_MSG_RESULT([no]); have_pic_shared=no])
      if test x"$have_pic_shared" != x"yes" -o x"$ac_cv_search_dlopen" = x"no"; then
--- a/gcc/configure
+++ b/gcc/configure
@@ -30375,6 +30375,9 @@ fi
    pluginlibs=
    plugin_check=yes
 
+   PICFLAG="-fPIC"
+   UNDEFINEDPREAMBLE="extern int X;"
+   UNDEFINEDCODE="return X == 0;"
    case "${host}" in
      *-*-mingw*)
        # Since plugin support under MinGW is not as straightforward as on
@@ -30397,6 +30400,11 @@ fi
 	 export_sym_check=
        fi
      ;;
+     *-*-mingw*|*-*-cygwin*|*-*-msys*)
+       PICFLAG=""
+       UNDEFINEDPREAMBLE=""
+       UNDEFINEDCODE=""
+     ;;
      *)
        if test x$build = x$host; then
 	 export_sym_check="objdump${exeext} -T"
@@ -30509,23 +30517,23 @@ fi
      case "${host}" in
        *-*-darwin*)
 	 CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g`
-	 CFLAGS="$CFLAGS -fPIC"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
 	 LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup"
        ;;
        *)
-	 CFLAGS="$CFLAGS -fPIC"
-	 LDFLAGS="$LDFLAGS -fPIC -shared"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
+	 LDFLAGS="$LDFLAGS ${PICFLAG} -shared"
        ;;
      esac
-     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fPIC -shared" >&5
-$as_echo_n "checking for -fPIC -shared... " >&6; }
+     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${PICFLAG} -shared" >&5
+$as_echo_n "checking for ${PICFLAG} -shared... " >&6; }
      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-extern int X;
+${UNDEFINEDPREAMBLE}
 int
 main ()
 {
-return X == 0;
+${UNDEFINEDCODE}
   ;
   return 0;
 }
--- a/libcc1/configure
+++ b/libcc1/configure
@@ -14795,6 +14795,9 @@ fi
    pluginlibs=
    plugin_check=yes
 
+   PICFLAG="-fPIC"
+   UNDEFINEDPREAMBLE="extern int X;"
+   UNDEFINEDCODE="return X == 0;"
    case "${host}" in
      *-*-mingw*)
        # Since plugin support under MinGW is not as straightforward as on
@@ -14817,6 +14820,11 @@ fi
 	 export_sym_check=
        fi
      ;;
+     *-*-mingw*|*-*-cygwin*|*-*-msys*)
+       PICFLAG=""
+       UNDEFINEDPREAMBLE=""
+       UNDEFINEDCODE=""
+     ;;
      *)
        if test x$build = x$host; then
 	 export_sym_check="objdump${exeext} -T"
@@ -14929,23 +14937,23 @@ fi
      case "${host}" in
        *-*-darwin*)
 	 CFLAGS=`echo $CFLAGS | sed s/-mdynamic-no-pic//g`
-	 CFLAGS="$CFLAGS -fPIC"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
 	 LDFLAGS="$LDFLAGS -shared -undefined dynamic_lookup"
        ;;
        *)
-	 CFLAGS="$CFLAGS -fPIC"
-	 LDFLAGS="$LDFLAGS -fPIC -shared"
+	 CFLAGS="$CFLAGS ${PICFLAG}"
+	 LDFLAGS="$LDFLAGS ${PICFLAG} -shared"
        ;;
      esac
-     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fPIC -shared" >&5
-$as_echo_n "checking for -fPIC -shared... " >&6; }
+     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${PICFLAG} -shared" >&5
+$as_echo_n "checking for ${PICFLAG} -shared... " >&6; }
      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-extern int X;
+${UNDEFINEDPREAMBLE}
 int
 main ()
 {
-return X == 0;
+${UNDEFINEDCODE}
   ;
   return 0;
 }