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diff --git a/sysdeps/unix/sysv/linux/i386/fpu_control.h b/sysdeps/unix/sysv/linux/i386/fpu_control.h
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+++ b/sysdeps/unix/sysv/linux/i386/fpu_control.h
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+/* Copyright (C) 1993 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Contributed by Olaf Flebbe.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#ifndef _FPU_CONTROL_H
+#define _FPU_CONTROL_H
+
+/* Here is the dirty part. Settup up your 387 through the control word
+ * (cw) register. 
+ *
+ *     15-13    12  11-10  9-8     7-6     5    4    3    2    1    0
+ * | reserved | IC | RC  | PC | reserved | PM | UM | OM | ZM | DM | IM
+ *
+ * IM: Invalid operation mask
+ * DM: Denormalized operand mask
+ * ZM: Zero-divide mask
+ * OM: Overflow mask
+ * UM: Underflow mask
+ * PM: Precision (inexact result) mask
+ * 
+ * Mask bit is 1 means no interrupt.
+ *
+ * PC: Precision control
+ * 11 - round to extended precision
+ * 10 - round to double precision
+ * 00 - round to single precision
+ *
+ * RC: Rounding control
+ * 00 - rounding to nearest
+ * 01 - rounding down (toward - infinity)
+ * 10 - rounding up (toward + infinity)
+ * 11 - rounding toward zero
+ *
+ * IC: Infinity control
+ * That is for 8087 and 80287 only.
+ *
+ * The hardware default is 0x037f. I choose 0x1372.
+ */
+
+#include <features.h>
+
+/* masking of interrupts */
+#define _FPU_MASK_IM  0x01  
+#define _FPU_MASK_DM  0x02
+#define _FPU_MASK_ZM  0x04
+#define _FPU_MASK_OM  0x08
+#define _FPU_MASK_UM  0x10
+#define _FPU_MASK_PM  0x20
+
+/* precision control */
+#define _FPU_EXTENDED 0x300   /* RECOMMENDED */
+#define _FPU_DOUBLE   0x200
+#define _FPU_SINGLE   0x0     /* DO NOT USE */
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x0    /* RECOMMENDED */
+#define _FPU_RC_DOWN    0x400
+#define _FPU_RC_UP      0x800
+#define _FPU_RC_ZERO    0xC00
+
+#define _FPU_RESERVED 0xF0C0  /* Reserved bits in cw */
+
+
+/* Now two recommended cw */
+
+/* Linux default:
+     - extended precision
+     - rounding to nearest
+     - exceptions on overflow, zero divide and NaN */
+#define _FPU_DEFAULT  0x1372 
+
+/* IEEE:  same as above, but exceptions */
+#define _FPU_IEEE     0x137f
+
+/* private namespace. It should only be used in init-first.o. */
+extern unsigned short __fpu_control;
+
+__BEGIN_DECLS
+
+/* called in init-first.o. It can be used to manipulate 387 control word. */
+extern void __setfpucw __P ((unsigned short));
+
+__END_DECLS
+
+#endif	/* fpu_control.h */