re PR target/47997 (gcc on macosx: "ld: warning: -fwritable-strings not compatible with literal CF/NSString")


gcc/objc:

	PR target/47997
	* objc-act.c (objc_build_string_object): Remove redundant second
	call to fix_string_type ().  Add a checking assert that we are,
	indeed, passed a STRING_CST.

From-SVN: r180653