* builtin-types.def (BT_FN_STRING_CONST_STRING): New builtin type.
	(BT_FN_PTR_SIZE_SIZE): Likewise.
	* builtins.def (BUILT_IN_MALLOC, BUILT_IN_CALLOC, BUILT_IN_STRDUP):
	New built-in functions for malloc, calloc and strdup respectively.
	* calls.c (special_function_p): No need to handle malloc-like
	functions any longer.  ECF_MALLOC is set via built-in attributes.

	* c-decl.c (duplicate_decls): Preserve pure and malloc attributes.
	* cp/decl.c (duplicate_decls): Preserve pure and malloc attributes.
	* f/com.c (duplicate_decls): Preserve pure and malloc attributes.

	* doc/extend.texi: Document these new built-in functions.

	* gcc.dg/builtins-13.c: New test case.
	* gcc.dg/builtins-14.c: New test case.

From-SVN: r65560