abs function question

Steve Ellcey sje@cup.hp.com
Tue Jul 29 00:13:00 GMT 2003


I am currently running into a problem with the function abs and the
header std_cstdlib.h.  This file contains the lines:

   namespace std
   {
	using ::abs
   }

The problem is that my system's stdlib.h header file is smart enough to
not do an extern declaration for abs if it is in C++ mode and instead
does an inline declaration of the abs function.  It only does an extern
declaration if it is in C mode.  Thus I get an error on the 'using ::abs'
line.  I could handle this with fixheaders but I was wondering if there
is any reason one couldn't replace

	using ::abs
with
	inline int abs(int __i) { return __i >= 0 ? __i : -__i; }


For that matter would it also make sense to replace


	inline long abs(long __i) { return labs(__i); }
with
	inline long abs(long __i) { return __i >= 0 ? __i : -__i; }


We already use this inline for the type 'long long'.

Steve Ellcey
sje@cup.hp.com



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