Robust detection of endianness at compile time.

[Tim Prince]

Ian Lance Taylor wrote:
> Andrew Haley <aph-gcc@littlepinkcloud.COM> writes:
>
>   
>> AC_C_BIGENDIAN is for integers.  As far as I am aware the PDP/ARM
>> "middle-endian" problem only applies to floating-point words, and the
>> situation for those is far more complex than mere endianness.  Not
>> every platform supports the IEEE-754 format, and picking apart other
>> formats requires special-case programming.  Happily, this isn't a
>> problem that most people have to solve.
>>     
Plauger's "Standard C Library" used short data types throughout when 
manipulating float and double, as VAX/ MIPS style data were still in 
fairly widespread use.  I guess a phase of history has passed when no 
one invokes the way VAX and MIPS did things.  Plauger's code would have 
worked for PDP; I wasn't aware of ARM floating point.