RFA: Enable DFP/BID on i?86-pc-mingw32 target

[Danny Smith <dannysmith@clear.net.nz>]

Hello,

With following patch libbid builds and passes all supported tests in
gcc.dg/dfp 

make -k check-gcc RUNSTESTFLAGS="dfp.exp"

		=== gcc Summary ===

# of expected passes		591
# of unsupported tests		1
/develop/svn/trunk/build/gcc/xgcc  version 4.3.0 200707158
(experimental)

I have also tried on cygwin target, but the build fails because of lack
of fenv.h,
included from libdecnumber/dec/Except.[ch].

Is this OK for mainline? 

2007-07-19  Danny Smith  <dannysmith@users.sourceforge.net>

gcc
	* configure.ac (i?86*-*-mingw*): Default enable_decimal_float to
bid.
	* configure: Regenerate
	
libgcc
	* config/t-dfprules: New file, copied from gcc/config.
	* config.host (i?86*-*-mingw*): Adds t-dfprules to tmake_file.


Index: gcc/configure.ac
===================================================================
--- gcc/configure.ac	(revision 126718)
+++ gcc/configure.ac	(working copy)
@@ -592,6 +592,9 @@
     powerpc*-*-linux* | i?86*-*-linux* | x86_64*-*-linux*)
       enable_decimal_float=yes
       ;;
+    i?86*-*-mingw*)
+      enable_decimal_float=yes
+      ;;
     *)
       AC_MSG_WARN(decimal float is not supported for this target,
ignored)
       enable_decimal_float=no
@@ -610,6 +613,9 @@
       i?86*-*-linux* | x86_64*-*-linux*)
 	enable_decimal_float=bid
 	;;
+      i?86*-*-mingw*)
+        enable_decimal_float=bid
+        ;;
       *)
 	enable_decimal_float=dpd
 	;;
Index: libgcc/config.host
===================================================================
--- libgcc/config.host	(revision 126718)
+++ libgcc/config.host	(working copy)
@@ -369,10 +369,14 @@
 	;;
 i[34567]86-*-pe)
 	;;
-i[34567]86-*-cygwin* | i[34567]86-*-mingw*)
+i[34567]86-*-cygwin*)
 	extra_parts="crtbegin.o crtend.o crtfastmath.o"
 	tmake_file="i386/t-cygming i386/t-crtfm"
 	;;
+i[34567]86-*-mingw*)
+	extra_parts="crtbegin.o crtend.o crtfastmath.o"
+	tmake_file="i386/t-cygming i386/t-crtfm t-dfprules"
+	;;
 x86_64-*-mingw*)
 	;;
 i[34567]86-*-uwin*)
Index: libgcc/config/t-dfprules
===================================================================
--- libgcc/config/t-dfprules	(revision 0)
+++ libgcc/config/t-dfprules	(revision 0)
@@ -0,0 +1,10 @@
+# Use DFP_ENABLE to build decimal floating point support routines for
+# all decimal floating point types (32-bit, 64-bit and 128-bit). We
+# use `true' for clarity, but any value will do.
+#
+DFP_ENABLE = true
+
+# DFP_CFLAGS can be used to pass target-specific CFLAGS when compiling
+# dfp-bit.c.  This is useful for overriding the definition of macros.
+#
+# DFP_CFLAGS = -DFOO=bar