Patch from Atsushi Nemoto (with some additions):

Current uClibc contains only one fpu_control.h and it is i386 version.
This is a patch to use platform specific fpu_control.h.  All new files
come from glibc 2.3.2.  This patch is against 0.9.21 but also can be
applied to CVS as is.

18 files changed, 722 insertions, 2 deletions

diff --git a/libc/sysdeps/linux/alpha/Makefile b/libc/sysdeps/linux/alpha/Makefile
index c94c9751f..85c530999 100644
--- a/libc/sysdeps/linux/alpha/Makefile
+++ b/libc/sysdeps/linux/alpha/Makefile
@@ -54,6 +54,7 @@ $(COBJS): %.o : %.c
 	$(STRIPTOOL) -x -R .note -R .comment $*.o
 
 headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/alpha/fpu_control.h .
 
 
 clean:
diff --git a/libc/sysdeps/linux/alpha/fpu_control.h b/libc/sysdeps/linux/alpha/fpu_control.h
new file mode 100644
index 000000000..28acdf170
--- /dev/null
+++ b/libc/sysdeps/linux/alpha/fpu_control.h
@@ -0,0 +1,106 @@
+/* FPU control word bits.  Alpha-mapped-to-Intel version.
+   Copyright (C) 1996, 1998, 2000, 2002 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _ALPHA_FPU_CONTROL_H
+#define _ALPHA_FPU_CONTROL_H
+
+/*
+ * Since many programs seem to hardcode the values passed to __setfpucw()
+ * (rather than using the manifest constants) we emulate the x87 interface
+ * here (at least where this makes sense).
+ *
+ *     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 -- without effect on Alpha */
+#define _FPU_EXTENDED 0x300   /* RECOMMENDED */
+#define _FPU_DOUBLE   0x200
+#define _FPU_SINGLE   0x0     /* DO NOT USE */
+
+/*
+ * rounding control---notice that on the Alpha this affects only
+ * instructions with the dynamic rounding mode qualifier (/d).
+ */
+#define _FPU_RC_NEAREST 0x000 /* 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 positive infinity.  There is no /p instruction
+       qualifier.  By setting the dynamic rounding mode to +infinity,
+       one can use /d to get round to +infinity with no extra overhead
+       (so long as the default isn't changed, of course...)
+     - no exceptions enabled.  */
+
+#define _FPU_DEFAULT  0x137f
+
+/* IEEE:  same as above. */
+#define _FPU_IEEE     0x137f
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t;
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif	/* _ALPHA_FPU_CONTROL */
diff --git a/libc/sysdeps/linux/arm/Makefile b/libc/sysdeps/linux/arm/Makefile
index beed16b23..038b994a2 100644
--- a/libc/sysdeps/linux/arm/Makefile
+++ b/libc/sysdeps/linux/arm/Makefile
@@ -62,6 +62,7 @@ gcrt1.o: $(CRT0_DEPS)
 endif
 
 headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/arm/fpu_control.h .
 
 
 clean:
diff --git a/libc/sysdeps/linux/arm/fpu_control.h b/libc/sysdeps/linux/arm/fpu_control.h
new file mode 100644
index 000000000..65912e496
--- /dev/null
+++ b/libc/sysdeps/linux/arm/fpu_control.h
@@ -0,0 +1,102 @@
+/* FPU control word definitions.  ARM version.
+   Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+/* We have a slight terminology confusion here.  On the ARM, the register
+ * we're interested in is actually the FPU status word - the FPU control
+ * word is something different (which is implementation-defined and only
+ * accessible from supervisor mode.)
+ *
+ * The FPSR looks like this:
+ *
+ *     31-24        23-16          15-8              7-0
+ * | system ID | trap enable | system control | exception flags |
+ *
+ * We ignore the system ID bits; for interest's sake they are:
+ *
+ *  0000	"old" FPE
+ *  1000	FPPC hardware
+ *  0001	FPE 400
+ *  1001	FPA hardware
+ *
+ * The trap enable and exception flags are both structured like this:
+ *
+ *     7 - 5     4     3     2     1     0
+ * | reserved | INX | UFL | OFL | DVZ | IVO |
+ *
+ * where a `1' bit in the enable byte means that the trap can occur, and
+ * a `1' bit in the flags byte means the exception has occurred.
+ *
+ * The exceptions are:
+ *
+ *  IVO - invalid operation
+ *  DVZ - divide by zero
+ *  OFL - overflow
+ *  UFL - underflow
+ *  INX - inexact (do not use; implementations differ)
+ *
+ * The system control byte looks like this:
+ *
+ *     7-5      4    3    2    1    0
+ * | reserved | AC | EP | SO | NE | ND |
+ *
+ * where the bits mean
+ *
+ *  ND - no denormalised numbers (force them all to zero)
+ *  NE - enable NaN exceptions
+ *  SO - synchronous operation
+ *  EP - use expanded packed-decimal format
+ *  AC - use alternate definition for C flag on compare operations
+ */
+
+/* masking of interrupts */
+#define _FPU_MASK_IM	0x00010000	/* invalid operation */
+#define _FPU_MASK_ZM	0x00020000	/* divide by zero */
+#define _FPU_MASK_OM	0x00040000	/* overflow */
+#define _FPU_MASK_UM	0x00080000	/* underflow */
+#define _FPU_MASK_PM	0x00100000	/* inexact */
+#define _FPU_MASK_DM	0x00000000	/* denormalized operation */
+
+/* The system id bytes cannot be changed.
+   Only the bottom 5 bits in the trap enable byte can be changed.
+   Only the bottom 5 bits in the system control byte can be changed.
+   Only the bottom 5 bits in the exception flags are used.
+   The exception flags are set by the fpu, but can be zeroed by the user. */
+#define _FPU_RESERVED	0xffe0e0e0	/* These bits are reserved.  */
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+   no interrupts for exceptions, rounding to nearest.  Changing the
+   rounding mode will break long double I/O.  Turn on the AC bit,
+   the compiler generates code that assumes it is on.  */
+#define _FPU_DEFAULT	0x00001000	/* Default value.  */
+#define _FPU_IEEE	0x001f1000	/* Default + exceptions enabled. */
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t;
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) __asm__ ("rfs %0" : "=r" (cw))
+#define _FPU_SETCW(cw) __asm__ ("wfs %0" : : "r" (cw))
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */
diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile
index 5323df366..8bff24f2e 100644
--- a/libc/sysdeps/linux/common/Makefile
+++ b/libc/sysdeps/linux/common/Makefile
@@ -54,7 +54,7 @@ endif
 
 OBJ=$(COBJS) $(MOBJ)
 
-all: $(STR_SYSCALLS) $(OBJ) $(LIBC)
+all: $(STR_SYSCALLS) $(OBJ) $(LIBC) headers
 
 $(LIBC): ar-target
 
@@ -98,6 +98,9 @@ $(TOPDIR)lib/crtn.o:
 	$(AR) $(ARFLAGS) $(TOPDIR)lib/crtn.o
 endif
 
+headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/common/fpu_control.h .
+
 clean:
 	rm -f *.[oa] *~ core crt[in].* *.S
 
diff --git a/libc/sysdeps/linux/common/fpu_control.h b/libc/sysdeps/linux/common/fpu_control.h
new file mode 100644
index 000000000..4a1b07d23
--- /dev/null
+++ b/libc/sysdeps/linux/common/fpu_control.h
@@ -0,0 +1,39 @@
+/* FPU control word definitions.  Stub version.
+   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+#define _FPU_RESERVED 0xffffffff    /* These bits are reserved and not changed.  */
+
+/* The fdlibm code requires no interrupts for exceptions.  Don't
+   change the rounding mode, it would break long double I/O!  */
+#define _FPU_DEFAULT  0x00000000 /* Default value.  */
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t;
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) 0
+#define _FPU_SETCW(cw) do { } while (0)
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */
diff --git a/libc/sysdeps/linux/i386/Makefile b/libc/sysdeps/linux/i386/Makefile
index 11df4cbb0..2f721eb6e 100644
--- a/libc/sysdeps/linux/i386/Makefile
+++ b/libc/sysdeps/linux/i386/Makefile
@@ -65,6 +65,7 @@ gcrt1.o: $(CRT0_DEPS)
 endif
 
 headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/i386/fpu_control.h .
 
 
 clean:
diff --git a/libc/sysdeps/linux/i386/fpu_control.h b/libc/sysdeps/linux/i386/fpu_control.h
new file mode 100644
index 000000000..ed9bf388a
--- /dev/null
+++ b/libc/sysdeps/linux/i386/fpu_control.h
@@ -0,0 +1,98 @@
+/* FPU control word bits.  i387 version.
+   Copyright (C) 1993,1995,1996,1997,1998,2000,2001 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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	1
+
+/* Here is the dirty part. Set 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 which we use.
+ */
+
+#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	/* libm requires double extended precision.  */
+#define _FPU_DOUBLE   0x200
+#define _FPU_SINGLE   0x0
+
+/* 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 */
+
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+   and no interrupts for exceptions, rounding to nearest.  */
+
+#define _FPU_DEFAULT  0x037f
+
+/* IEEE:  same as above.  */
+#define _FPU_IEEE     0x037f
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__HI__)));
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) __asm__ ("fnstcw %0" : "=m" (*&cw))
+#define _FPU_SETCW(cw) __asm__ ("fldcw %0" : : "m" (*&cw))
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif	/* fpu_control.h */
diff --git a/libc/sysdeps/linux/m68k/Makefile b/libc/sysdeps/linux/m68k/Makefile
index a98352198..7369bc925 100644
--- a/libc/sysdeps/linux/m68k/Makefile
+++ b/libc/sysdeps/linux/m68k/Makefile
@@ -65,6 +65,7 @@ ifneq ($(strip $(HAVE_ELF)),y)
 	echo "Working around compiler bug in the m68k-pic-coff toolchain"
 	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/m68k/float.h .
 endif
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/m68k/fpu_control.h .
 
 
 clean:
diff --git a/libc/sysdeps/linux/m68k/fpu_control.h b/libc/sysdeps/linux/m68k/fpu_control.h
new file mode 100644
index 000000000..1b2ba87c9
--- /dev/null
+++ b/libc/sysdeps/linux/m68k/fpu_control.h
@@ -0,0 +1,69 @@
+/* FPU control word definitions.  PowerPC version.
+   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x00   /* RECOMMENDED */
+#define _FPU_RC_DOWN    0x03
+#define _FPU_RC_UP      0x02
+#define _FPU_RC_ZERO    0x01
+
+#define _FPU_MASK_NI  0x04 /* non-ieee mode */
+
+/* masking of interrupts */
+#define _FPU_MASK_ZM  0x10 /* zero divide */
+#define _FPU_MASK_OM  0x40 /* overflow */
+#define _FPU_MASK_UM  0x20 /* underflow */
+#define _FPU_MASK_XM  0x08 /* inexact */
+#define _FPU_MASK_IM  0x80 /* invalid operation */
+
+#define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */
+
+/* The fdlibm code requires no interrupts for exceptions.  */
+#define _FPU_DEFAULT  0x00000000 /* Default value.  */
+
+/* IEEE:  same as above, but (some) exceptions;
+   we leave the 'inexact' exception off.
+ */
+#define _FPU_IEEE     0x000000f0
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(__cw) ( { \
+  union { double d; fpu_control_t cw[2]; } \
+    tmp __attribute__ ((__aligned__(8))); \
+  __asm__ ("mffs 0; stfd%U0 0,%0" : "=m" (tmp.d) : : "fr0"); \
+  (__cw)=tmp.cw[1]; \
+  tmp.cw[1]; } )
+#define _FPU_SETCW(__cw) { \
+  union { double d; fpu_control_t cw[2]; } \
+    tmp __attribute__ ((__aligned__(8))); \
+  tmp.cw[0] = 0xFFF80000; /* More-or-less arbitrary; this is a QNaN. */ \
+  tmp.cw[1] = __cw; \
+  __asm__ ("lfd%U0 0,%0; mtfsf 255,0" : : "m" (tmp.d) : "fr0"); \
+}
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */
diff --git a/libc/sysdeps/linux/mips/Makefile b/libc/sysdeps/linux/mips/Makefile
index eaeff33b7..a226a8466 100644
--- a/libc/sysdeps/linux/mips/Makefile
+++ b/libc/sysdeps/linux/mips/Makefile
@@ -55,6 +55,7 @@ $(COBJS): %.o : %.c
 headers:
 	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/mips/sgidefs.h .
 #	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/mips/regdef.h .
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/mips/fpu_control.h .
 
 clean:
 	rm -f *.[oa] *~ core
diff --git a/libc/sysdeps/linux/mips/fpu_control.h b/libc/sysdeps/linux/mips/fpu_control.h
new file mode 100644
index 000000000..da18deab5
--- /dev/null
+++ b/libc/sysdeps/linux/mips/fpu_control.h
@@ -0,0 +1,98 @@
+/* FPU control word bits.  Mips version.
+   Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Olaf Flebbe and Ralf Baechle.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+/* MIPS FPU floating point control register bits.
+ *
+ * 31-25  -> floating point conditions code bits 7-1.  These bits are only
+ *           available in MIPS IV.
+ * 24     -> flush denormalized results to zero instead of
+ *           causing unimplemented operation exception.  This bit is only
+ *           available for MIPS III and newer.
+ * 23     -> Condition bit
+ * 22-18  -> reserved (read as 0, write with 0)
+ * 17     -> cause bit for unimplemented operation
+ * 16     -> cause bit for invalid exception
+ * 15     -> cause bit for division by zero exception
+ * 14     -> cause bit for overflow exception
+ * 13     -> cause bit for underflow exception
+ * 12     -> cause bit for inexact exception
+ * 11     -> enable exception for invalid exception
+ * 10     -> enable exception for division by zero exception
+ *  9     -> enable exception for overflow exception
+ *  8     -> enable exception for underflow exception
+ *  7     -> enable exception for inexact exception
+ *  6     -> flag invalid exception
+ *  5     -> flag division by zero exception
+ *  4     -> flag overflow exception
+ *  3     -> flag underflow exception
+ *  2     -> flag inexact exception
+ *  1-0   -> rounding control
+ *
+ *
+ * Rounding Control:
+ * 00 - rounding to nearest (RN)
+ * 01 - rounding toward zero (RZ)
+ * 10 - rounding (up) toward plus infinity (RP)
+ * 11 - rounding (down)toward minus infinity (RM)
+ */
+
+#include <features.h>
+
+/* masking of interrupts */
+#define _FPU_MASK_V     0x0800  /* Invalid operation */
+#define _FPU_MASK_Z     0x0400  /* Division by zero  */
+#define _FPU_MASK_O     0x0200  /* Overflow          */
+#define _FPU_MASK_U     0x0100  /* Underflow         */
+#define _FPU_MASK_I     0x0080  /* Inexact operation */
+
+/* flush denormalized numbers to zero */
+#define _FPU_FLUSH_TZ   0x1000000
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x0     /* RECOMMENDED */
+#define _FPU_RC_ZERO    0x1
+#define _FPU_RC_UP      0x2
+#define _FPU_RC_DOWN    0x3
+
+#define _FPU_RESERVED 0xfe3c0000  /* Reserved bits in cw */
+
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+   and no interrupts for exceptions, rounding to nearest.  */
+
+#define _FPU_DEFAULT  0x00000000
+
+/* IEEE:  same as above, but exceptions */
+#define _FPU_IEEE     0x00000F80
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) __asm__ ("cfc1 %0,$31" : "=r" (cw))
+#define _FPU_SETCW(cw) __asm__ ("ctc1 %0,$31" : : "r" (cw))
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif	/* fpu_control.h */
diff --git a/libc/sysdeps/linux/powerpc/Makefile b/libc/sysdeps/linux/powerpc/Makefile
index c1cd0055c..e9798cf7b 100644
--- a/libc/sysdeps/linux/powerpc/Makefile
+++ b/libc/sysdeps/linux/powerpc/Makefile
@@ -65,7 +65,7 @@ gcrt1.o: $(CRT0_DEPS)
 endif
 
 headers:
-
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/powerpc/fpu_control.h .
 
 clean:
 	rm -f *.[oa] *~ core
diff --git a/libc/sysdeps/linux/powerpc/fpu_control.h b/libc/sysdeps/linux/powerpc/fpu_control.h
new file mode 100644
index 000000000..1b2ba87c9
--- /dev/null
+++ b/libc/sysdeps/linux/powerpc/fpu_control.h
@@ -0,0 +1,69 @@
+/* FPU control word definitions.  PowerPC version.
+   Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x00   /* RECOMMENDED */
+#define _FPU_RC_DOWN    0x03
+#define _FPU_RC_UP      0x02
+#define _FPU_RC_ZERO    0x01
+
+#define _FPU_MASK_NI  0x04 /* non-ieee mode */
+
+/* masking of interrupts */
+#define _FPU_MASK_ZM  0x10 /* zero divide */
+#define _FPU_MASK_OM  0x40 /* overflow */
+#define _FPU_MASK_UM  0x20 /* underflow */
+#define _FPU_MASK_XM  0x08 /* inexact */
+#define _FPU_MASK_IM  0x80 /* invalid operation */
+
+#define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */
+
+/* The fdlibm code requires no interrupts for exceptions.  */
+#define _FPU_DEFAULT  0x00000000 /* Default value.  */
+
+/* IEEE:  same as above, but (some) exceptions;
+   we leave the 'inexact' exception off.
+ */
+#define _FPU_IEEE     0x000000f0
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__)));
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(__cw) ( { \
+  union { double d; fpu_control_t cw[2]; } \
+    tmp __attribute__ ((__aligned__(8))); \
+  __asm__ ("mffs 0; stfd%U0 0,%0" : "=m" (tmp.d) : : "fr0"); \
+  (__cw)=tmp.cw[1]; \
+  tmp.cw[1]; } )
+#define _FPU_SETCW(__cw) { \
+  union { double d; fpu_control_t cw[2]; } \
+    tmp __attribute__ ((__aligned__(8))); \
+  tmp.cw[0] = 0xFFF80000; /* More-or-less arbitrary; this is a QNaN. */ \
+  tmp.cw[1] = __cw; \
+  __asm__ ("lfd%U0 0,%0; mtfsf 255,0" : : "m" (tmp.d) : "fr0"); \
+}
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */
diff --git a/libc/sysdeps/linux/sh/Makefile b/libc/sysdeps/linux/sh/Makefile
index 758d4462d..b4266c9f5 100644
--- a/libc/sysdeps/linux/sh/Makefile
+++ b/libc/sysdeps/linux/sh/Makefile
@@ -64,6 +64,7 @@ gcrt1.o: $(CRT0_DEPS)
 endif
 
 headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/sh/fpu_control.h .
 
 clean:
 	rm -f *.[oa] *~ core
diff --git a/libc/sysdeps/linux/sh/fpu_control.h b/libc/sysdeps/linux/sh/fpu_control.h
new file mode 100644
index 000000000..43eb9e549
--- /dev/null
+++ b/libc/sysdeps/linux/sh/fpu_control.h
@@ -0,0 +1,56 @@
+/* FPU control word definitions.  SH version.
+   Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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
+
+/* masking of interrupts */
+#define _FPU_MASK_VM	0x0800	/* Invalid operation */
+#define _FPU_MASK_ZM	0x0400	/* Division by zero  */
+#define _FPU_MASK_OM	0x0200	/* Overflow	     */
+#define _FPU_MASK_UM	0x0100	/* Underflow	     */
+#define _FPU_MASK_IM	0x0080	/* Inexact operation */
+
+/* rounding control */
+#define _FPU_RC_NEAREST 0x0	/* RECOMMENDED */
+#define _FPU_RC_ZERO	0x1
+
+#define _FPU_RESERVED 0xffc00000  /* These bits are reserved.  */
+
+/* The fdlibm code requires strict IEEE double precision arithmetic,
+   and no interrupts for exceptions, rounding to nearest.  */
+#define _FPU_DEFAULT	0x00080000 /* Default value.  */
+#define _FPU_IEEE	0x00080f80 /* Default + exceptions enabled. */
+
+/* Type of the control word.  */
+typedef unsigned int fpu_control_t;
+
+/* Macros for accessing the hardware control word.  */
+#define _FPU_GETCW(cw) __asm__ ("sts fpscr,%0" : "=r" (cw))
+
+#if defined __GNUC__
+#define _FPU_SETCW(cw) __set_fpscr ((cw))
+#else
+#define _FPU_SETCW(cw) __asm__ ("lds %0,fpscr" : : "r" (cw))
+#endif
+
+/* Default control word set at startup.	 */
+extern fpu_control_t __fpu_control;
+
+#endif /* _FPU_CONTROL_H */
diff --git a/libc/sysdeps/linux/sparc/Makefile b/libc/sysdeps/linux/sparc/Makefile
index 1491cf343..19e9d9394 100644
--- a/libc/sysdeps/linux/sparc/Makefile
+++ b/libc/sysdeps/linux/sparc/Makefile
@@ -55,6 +55,7 @@ $(COBJS): %.o : %.c
 	$(STRIPTOOL) -x -R .note -R .comment $*.o
 
 headers:
+	cd $(TOPDIR)/include && ln -fs ../libc/sysdeps/linux/sparc/fpu_control.h .
 
 clean:
 	rm -f *.[oa] *~ core
diff --git a/libc/sysdeps/linux/sparc/fpu_control.h b/libc/sysdeps/linux/sparc/fpu_control.h
new file mode 100644
index 000000000..b29734ce2
--- /dev/null
+++ b/libc/sysdeps/linux/sparc/fpu_control.h
@@ -0,0 +1,73 @@
+/* FPU control word bits.  SPARC version.
+   Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Miguel de Icaza
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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	1
+
+
+#include <features.h>
+#include <bits/wordsize.h>
+
+/* masking of interrupts */
+#define _FPU_MASK_IM  0x08000000
+#define _FPU_MASK_OM  0x04000000
+#define _FPU_MASK_UM  0x02000000
+#define _FPU_MASK_ZM  0x01000000
+#define _FPU_MASK_PM  0x00800000
+
+/* precision control */
+#define _FPU_EXTENDED 0x00000000     /* RECOMMENDED */
+#define _FPU_DOUBLE   0x20000000
+#define _FPU_80BIT    0x30000000
+#define _FPU_SINGLE   0x10000000     /* DO NOT USE */
+
+/* rounding control / Sparc */
+#define _FPU_RC_DOWN    0xc0000000
+#define _FPU_RC_UP      0x80000000
+#define _FPU_RC_ZERO    0x40000000
+#define _FPU_RC_NEAREST 0x0        /* RECOMMENDED */
+
+#define _FPU_RESERVED   0x30300000  /* Reserved bits in cw */
+
+
+/* Now two recommended cw */
+
+/* Linux and IEEE default:
+     - extended precision
+     - rounding to nearest
+     - no exceptions  */
+#define _FPU_DEFAULT  0x0
+#define _FPU_IEEE     0x0
+
+/* Type of the control word.  */
+typedef unsigned long int fpu_control_t;
+
+#if __WORDSIZE == 64
+# define _FPU_GETCW(cw) __asm__ ("stx %%fsr,%0" : "=m" (*&cw))
+# define _FPU_SETCW(cw) __asm__ ("ldx %0,%%fsr" : : "m" (*&cw))
+#else
+# define _FPU_GETCW(cw) __asm__ ("st %%fsr,%0" : "=m" (*&cw))
+# define _FPU_SETCW(cw) __asm__ ("ld %0,%%fsr" : : "m" (*&cw))
+#endif
+
+/* Default control word set at startup.  */
+extern fpu_control_t __fpu_control;
+
+#endif	/* fpu_control.h */