PR symtab/17391 gdb internal error: assertion fails in regcache.c:178

gdb/ChangeLog:

	* dwarf2-frame.c (dwarf2_restore_rule): Call dwarf_reg_to_regnum
	instead of gdbarch_dwarf2_reg_to_regnum.
	(dwarf2_frame_cache): Ditto.
	(read_addr_from_reg): Call dwarf_reg_to_regnum_or_error instead of
	gdbarch_dwarf2_reg_to_regnum.
	(get_reg_value): Ditto.
	(dwarf2_fetch_cfa_info): Ditto.
	(dwarf2_frame_prev_register): Ditto.
	* dwarf2loc.c: #include "complaints.h".
	(dwarf_expr_read_addr_from_reg): Call dwarf_reg_to_regnum_or_error
	instead of gdbarch_dwarf2_reg_to_regnum.
	(dwarf_expr_get_reg_value): Ditto.
	(read_pieced_value): Ditto.
	(write_pieced_value): Ditto.
	(dwarf2_evaluate_loc_desc_full): Ditto.
	(dwarf_reg_to_regnum): New function.
	(throw_bad_regnum_error): New function.
	(dwarf_reg_to_regnum_or_error): Renamed from
	dwarf2_reg_to_regnum_or_errorChange to take a ULONGEST regnum.
	All callers updated.  Call throw_bad_regnum_error.
	(locexpr_regname): Improve text of bad register number.
	* dwarf2loc.h (dwarf_reg_to_regnum): Declare.
	(dwarf_reg_to_regnum_or_error): Update prototype.
	* dwarf2expr.c: #include "dwarf2loc.h".
	(dwarf_block_to_sp_offset): Call dwarf_reg_to_regnum instead of
	gdbarch_dwarf2_reg_to_regnum.
	* gdbarch.sh (dwarf2_reg_to_regnum): Add comment.
	* gdbarch.h: Regenerate.
	* amd64-tdep.c (amd64_dwarf_reg_to_regnum): Remove warning for bad
	register.
	* avr-tdep.c (avr_dwarf_reg_to_regnum): Ditto.
	* cris-tdep.c (cris_dwarf2_reg_to_regnum): Ditto.
	* bfin-tdep.c (bfin_reg_to_regnum): Fix error checking.
	* hppa-linux-tdep.c (hppa_dwarf_reg_to_regnum): Improve error checking.
	Remove warning for bad register.
	* hppa-tdep.c (hppa64_dwarf_reg_to_regnum): Ditto.
	* i386-tdep.c (i386_svr4_dwarf_reg_to_regnum): Renamed from
	i386_svr4_reg_to_regnum.  Return -1 for bad registers.
	(i386_svr4_reg_to_regnum): New function.
	(i386_gdbarch_init): Update call to set_gdbarch_dwarf2_reg_to_regnum.
	* microblaze-tdep.c (microblaze_dwarf2_reg_to_regnum): Don't assert
	on bad registers, return -1.
	* msp430-tdep.c (msp430_dwarf2_reg_to_regnum): Improve error checking.
	Remove warning for bad register.
	* nios2-tdep.c: Add static assert for NIOS2_NUM_REGS.
	(nios2_dwarf_reg_to_regnum): Fix off-by-one error.
	Remove warning for bad register.  Return -1 for bad register.
	* rl78-tdep.c (rl78_dwarf_reg_to_regnum): Don't flag an internal error
	for bad register, return -1.
	* rx-tdep.c (rx_dwarf_reg_to_regnum): Ditto.
	* m68k-tdep.c (m68k_dwarf_reg_to_regnum): Fix error result.
	* mep-tdep.c (mep_debug_reg_to_regnum): Ditto.
	* mips-tdep.c (mips_stab_reg_to_regnum): Ditto.
	(mips_dwarf_dwarf2_ecoff_reg_to_regnum): Ditto.
	* mn10300-tdep.c (mn10300_dwarf2_reg_to_regnum): Remove warning
	for bad regs.
	* xtensa-tdep.c (xtensa_reg_to_regnum): Remove internal error for
	bad regs.  Fix error result.
	* stabsread.c (stab_reg_to_regnum): Watch for negative regno.
	(reg_value_complaint): Update complaint text.
	* mdebugread.c (reg_value_complaint): New function.
	(mdebug_reg_to_regnum): Rewrite to watch for bad reg numbers.

gdb/testsuite/ChangeLog:

	* lib/dwarf.exp (_location): Add support for DW_OP_regx.
	* gdb.dwarf2/bad-regnum.c: New file.
	* gdb.dwarf2/bad-regnum.exp: New file.

gdb/stabsread.c

@@ -169,7 +169,7 @@ static void
 reg_value_complaint (int regnum, int num_regs, const char *sym)
 {
   complaint (&symfile_complaints,
-	     _("register number %d too large (max %d) in symbol %s"),
+	     _("bad register number %d (max %d) in symbol %s"),
              regnum, num_regs - 1, sym);
 }
 
@@ -597,8 +597,9 @@ stab_reg_to_regnum (struct symbol *sym, struct gdbarch *gdbarch)
 {
   int regno = gdbarch_stab_reg_to_regnum (gdbarch, SYMBOL_VALUE (sym));
 
-  if (regno >= gdbarch_num_regs (gdbarch)
-		+ gdbarch_num_pseudo_regs (gdbarch))
+  if (regno < 0
+      || regno >= (gdbarch_num_regs (gdbarch)
+		   + gdbarch_num_pseudo_regs (gdbarch)))
     {
       reg_value_complaint (regno,
 			   gdbarch_num_regs (gdbarch)