Remove -fwritable-strings.

Remove -fwritable-strings.

gcc/
	Remove -fwritable-strings.
	* c-common.c (fix_string_type): Don't check
	flag_writable_strings.
	(fix_string_type): Likewise.
	* c-opts.c (set_std_c89): Don't initialize
	flag_writable_strings.
	(set_std_c99): Likewise.
	* common.opt (fwritable-strings): Remove.
	* flags.h: Remove the external declaration of
	flag_writable_strings.
	* opts.c (common_handle_option) <OPT_fwritable_strings>:
	Remove.
	* toplev.c (flag_writable_strings): Remove.
	(f_options): Remove an entry for writable-strings.
	* varasm.c (const_hash_1) <STRING_CST>: Don't check
	flag_writable_strings.
	(compare_constant) <STRING_CST>: Likewise.
	(build_constant_desc): Likewise.
	* config/darwin.c (machopic_select_section): Likewise.
	* config/arm/arm.c (AOF_ASSEMBLER): Likewise.
	* config/arm/pe.c (arm_pe_encode_section_info): Likewise.
	* config/iq2000/iq2000.c (iq2000_select_section): Likewise.
	* config/mips/mips.c (mips_select_section): Likewise.
	(mips_encode_section_info): Likewise.
	* config/pa/pa.c (pa_select_section): Likewise.
	* config/pa/pa.h (TEXT_SPACE_P): Likewise.
	* config/v850/v850.c (v850_select_section): Likewise.
	* doc/invoke.texi (-fwritable-strings): Remove.
	(-fno-const-strings): Don't mention -fwritable-strings.
	* doc/trouble.texi: Don't mention -fwritable-strings.

gcc/cp/
	* decl.c (cxx_init_decl_processing): Don't check
	flag_writable_strings.

gcc/testsuite/
	* gcc.dg/fwritable-strings-1.c: Remove.

Co-Authored-By: Kazu Hirata <kazu@cs.umass.edu>
From-SVN: r78333