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+?RCS: Copyright (c) 2012 Raphael Manfredi
+?RCS: You may redistribute only under the terms of the Artistic License,
+?RCS: as specified in the README file that comes with the distribution.
+?RCS: You may reuse parts of this distribution only within the terms of
+?RCS: that same Artistic License; a copy of which may be found at the root
+?RCS: of the source tree for dist 4.0.
+?MAKE:d_ieee754 ieee754_byteorder: cat contains echo n c \
+ Myread Oldconfig Loc Setvar +cc +ccflags rm _o
+?MAKE: -pick add $@ %<
+?S: This variable conditionally defines the USE_IEEE754_FLOAT symbol,
+?S: which indicates to the C program that floats and doubles use the
+?S: IEEE-754 format.
+?S: This variable holds the IEEE float byte order. In the following, larger
+?S: digits indicate more significance. The variable byteorder is either 4321
+?S: on a big-endian machine, or 1234 on a little-endian one.
+?S: cannot figure it out.
+?C: When defined, this symbol indicates that float and double values are
+?C: stored using the IEEE-754 floating point format. See IEEE754_BYTEORDER
+?C: to determine the endianness in case these values need to be serialized.
+?C: This symbol holds the hexadecimal constant defined in ieee754_byteorder,
+?C: i.e. 1234 for little-endian or 4321 for big-ending floats. It is 0 when
+?C: floats are not stored in IEEE-754 format.
+?H:#$d_ieee754 USE_IEEE754_FLOAT
+?H:#define IEEE754_BYTEORDER 0x$ieee754_byteorder /* large digits for MSB */
+?F:!str !try.c
+?LINT:set d_ieee754
+: check for ieee754 float and their endianness
+?X: An idea from Guido Draheim <> checking the endianness
+?X: without actually executing code, which allows cross-compiling.
+echo " "
+$echo $n "Checking IEEE-754 float byte-ordering...$c" >&4
+$cat >try.c <<'EOCP'
+float ascii_le[] = {
+ 3223.213134765625, 6.8273612896518898e-07, 1.9753562586009612e+31, 0 };
+float ascii_be[] = {
+ 865942.3125, 6.7652519659605424e+22, 1.9695089292781631e-07, 0 };
+if $cc -c $ccflags try.c >/dev/null 2>&1; then
+ if $contains ISieee754Sys try$_o >/dev/null 2>&1; then
+ val=$define
+ order=4321
+ elif $contains isIEEE754Sys try$_o >/dev/null 2>&1; then
+ val=$define
+ order=1234
+?X: On Solaris, "grep" does not work on binary files -- use strings.
+ else
+ strings try$_o >str 2>/dev/null
+ if $contains ISieee754Sys str >/dev/null 2>&1; then
+ val=$define
+ order=4321
+ elif $contains isIEEE754Sys str >/dev/null 2>&1; then
+ val=$define
+ order=1234
+ else
+ val=$undef
+ fi
+ $rm -f str
+ fi
+set d_ieee754
+eval $setvar
+case "$order" in
+0) echo " not using IEEE-754 here." >&4;;
+1234) echo " little-endian." >&4;;
+4321) echo " big-endian." >&4;;
+$rm -f try.c try$_o