avoid early asm output

avoid early asm output

This avoids early assembler output via the gimplifier creating
new static CTORs.  The output machinery seems to be prepared to
output constants recursively and it's just a matter of
appropriately defering or not defering output.

This also has the advantage of not outputting .string for
optimized away local aggregate initializers containing string
references.

2020-06-18  Richard Biener  <rguenther@suse.de>

	* varasm.c (assemble_variable): Make sure to not
	defer output when outputting addressed constants.
	(output_constant_def_contents): Likewise.
	(add_constant_to_table): Take and pass on whether to
	defer output.
	(output_addressed_constants): Likewise.
	(output_constant_def): Pass on whether to defer output
	to add_constant_to_table.
	(tree_output_constant_def): Defer output of constants.