include:
	* libiberty.h (concat_length, concat_copy, concat_copy2,
	libiberty_concat_ptr, ACONCAT): New.

libiberty:
	* concat.c (vconcat_length, vconcat_copy, concat_length,
	concat_copy, concat_copy2): New functions.
	(concat): Use vconcat_length/vconcat_copy.

gcc:
	* gcc.c (find_file): Use ACONCAT in lieu of alloca/strcpy/strcat.

From-SVN: r45664