re PR target/16304 (bootstrap failure on AIX 4.3.3: cannot build strstream in libstdc++)

re PR target/16304 (bootstrap failure on AIX 4.3.3: cannot build strstream in libstdc++)

	PR target/16304
	* defaults.h (TARGET_DEFERRED_OUTPUT_DEFS): Provide default.
	* toplev.c (compile_file): Call process_pending_assemble_output_defs
	just before targetm.asm_out.file_end.
	* tree.h (process_pending_assemble_output_defs): Declare.
	* varasm.c (assemble_output_def, process_pending_assemble_output_defs):
	New functions.
	(assemble_alias): Defer generation of assembly code for defines when
	TARGET_DEFERRED_OUTPUT_DEFS is true.
	* config/rs6000/aix41.h (TARGET_DEFERRED_OUTPUT_DEFS): Define.
	* config/rs6000/aix43.h (TARGET_DEFERRED_OUTPUT_DEFS): Define.
	* doc/tm.texi (TARGET_DEFERRED_OUTPUT_DEFS): document.

From-SVN: r93726