Apply 'const' in more places

Many global arrays in gdb could be marked "const" but are not.  This
patch changes some of them.  (There may be other arrays that could
benefit from this treatment.  I only examined arrays of strings.)

This lets the linker move some symbols to the readonly data section.
For example, previously:

0000000000000000 d _ZL18can_use_agent_enum

is now:

0000000000000030 r _ZL18can_use_agent_enum

2020-09-14  Tom Tromey  <tromey@adacore.com>

	* x86-tdep.h (x86_in_indirect_branch_thunk): Update.
	* x86-tdep.c (x86_is_thunk_register_name)
	(x86_in_indirect_branch_thunk): Update.
	* sparc64-tdep.c (sparc64_fpu_register_names)
	(sparc64_cp0_register_names, sparc64_register_names)
	(sparc64_pseudo_register_names): Now const.
	* sparc-tdep.h (struct gdbarch_tdep) <fpu_register_names,
	cp0_registers_num>: Now const.
	* sparc-tdep.c (sparc_core_register_names)
	(sparc32_fpu_register_names, sparc32_cp0_register_names)
	(sparc32_pseudo_register_names): Now const.
	(validate_tdesc_registers): Update.
	* rust-lang.c (rust_extensions): Now const.
	* p-lang.c (p_extensions): Now const.
	* objc-lang.c (objc_extensions): Now const.
	* nto-tdep.c (nto_thread_state_str): Now const.
	* moxie-tdep.c (moxie_register_names): Now const.
	* mips-tdep.h (struct gdbarch_tdep) <mips_processor_reg_names>:
	Now const.
	* mips-tdep.c (mips_generic_reg_names, mips_tx39_reg_names)
	(mips_linux_reg_names): Now const.
	(mips_gdbarch_init): Update.
	* microblaze-tdep.c (microblaze_register_names): Now const.
	* m68k-tdep.c (m68k_register_names): Now const.
	* m32r-tdep.c (m32r_register_names): Now const.
	* ia64-tdep.c (ia64_register_names): Now const.
	* i386-tdep.h (struct gdbarch_tdep) <register_names,
	ymmh_register_names, ymm16h_regnum, mpx_register_names,
	k_register_names, zmmh_register_names, xmm_avx512_register_names,
	ymm_avx512_register_names, pkeys_register_names>: Now const.
	* i386-tdep.c (i386_register_names, i386_zmm_names)
	(i386_zmmh_names, i386_k_names, i386_ymm_names, i386_ymmh_names)
	(i386_mpx_names, i386_pkeys_names, i386_bnd_names)
	(i386_mmx_names, i386_byte_names, i386_word_names): Now const.
	* f-lang.c (f_extensions): Now const.
	* d-lang.c (d_extensions): Now const.
	* csky-tdep.c (csky_register_names): Now const.
	* charset.c (default_charset_names, charset_enum): Now const.
	(_initialize_charset): Update.
	* c-lang.c (c_extensions, cplus_extensions, asm_extensions): Now
	const.
	* bsd-uthread.c (bsd_uthread_solib_names): Now const.
	(bsd_uthread_solib_loaded): Update.
	(bsd_uthread_state): Now const.
	* amd64-tdep.c (amd64_register_names, amd64_ymm_names)
	(amd64_ymm_avx512_names, amd64_ymmh_names)
	(amd64_ymmh_avx512_names, amd64_mpx_names, amd64_k_names)
	(amd64_zmmh_names, amd64_zmm_names, amd64_xmm_avx512_names)
	(amd64_pkeys_names, amd64_byte_names, amd64_word_names)
	(amd64_dword_names): Now const.
	* agent.c (can_use_agent_enum): Now const.
	* ada-tasks.c (task_states, long_task_states): Now const.
	* ada-lang.c (known_runtime_file_name_patterns)
	(known_auxiliary_function_name_patterns, attribute_names)
	(standard_exc, ada_extensions): Now const.

gdbserver/ChangeLog
2020-09-14  Tom Tromey  <tromey@adacore.com>

	* tracepoint.cc (eval_result_names): Now const.
	* ax.cc (gdb_agent_op_names): Now const.

1 files changed, 12 insertions, 6 deletions

diff --git a/gdb/sparc-tdep.c b/gdb/sparc-tdep.c
index 681b800..e3401fe 100644
--- a/gdb/sparc-tdep.c
+++ b/gdb/sparc-tdep.c
@@ -363,11 +363,17 @@ sparc_arg_by_memory_p (const struct type *type)
 #define SPARC32_CP0_REGISTERS \
   "y", "psr", "wim", "tbr", "pc", "npc", "fsr", "csr"
 
-static const char *sparc_core_register_names[] = { SPARC_CORE_REGISTERS };
-static const char *sparc32_fpu_register_names[] = { SPARC32_FPU_REGISTERS };
-static const char *sparc32_cp0_register_names[] = { SPARC32_CP0_REGISTERS };
+static const char * const sparc_core_register_names[] = {
+  SPARC_CORE_REGISTERS
+};
+static const char * const sparc32_fpu_register_names[] = {
+  SPARC32_FPU_REGISTERS
+};
+static const char * const sparc32_cp0_register_names[] = {
+  SPARC32_CP0_REGISTERS
+};
 
-static const char *sparc32_register_names[] =
+static const char * const sparc32_register_names[] =
 {
   SPARC_CORE_REGISTERS,
   SPARC32_FPU_REGISTERS,
@@ -380,7 +386,7 @@ static const char *sparc32_register_names[] =
 /* We provide the aliases %d0..%d30 for the floating registers as
    "psuedo" registers.  */
 
-static const char *sparc32_pseudo_register_names[] =
+static const char * const sparc32_pseudo_register_names[] =
 {
   "d0", "d2", "d4", "d6", "d8", "d10", "d12", "d14",
   "d16", "d18", "d20", "d22", "d24", "d26", "d28", "d30"
@@ -1784,7 +1790,7 @@ static int
 validate_tdesc_registers (const struct target_desc *tdesc,
                           struct tdesc_arch_data *tdesc_data,
                           const char *feature_name,
-                          const char *register_names[],
+                          const char * const register_names[],
                           unsigned int registers_num,
                           unsigned int reg_start)
 {