+ if (*DEPRECATED_SYMBOL_NAME (sym))
+ {
+ struct symbol *nsym;
+ nsym = lookup_symbol
+ (DEPRECATED_SYMBOL_NAME (sym),
+ b, VAR_DOMAIN, (int *) NULL, (struct symtab **) NULL);
+ if (SYMBOL_CLASS (nsym) == LOC_REGISTER)
+ {
+ /* There is a LOC_ARG/LOC_REGISTER pair. This means that
+ it was passed on the stack and loaded into a register,
+ or passed in a register and stored in a stack slot.
+ GDB 3.x used the LOC_ARG; GDB 4.0-4.11 used the LOC_REGISTER.
+
+ Reasons for using the LOC_ARG:
+ (1) because find_saved_registers may be slow for remote
+ debugging,
+ (2) because registers are often re-used and stack slots
+ rarely (never?) are. Therefore using the stack slot is
+ much less likely to print garbage.
+
+ Reasons why we might want to use the LOC_REGISTER:
+ (1) So that the backtrace prints the same value as
+ "print foo". I see no compelling reason why this needs
+ to be the case; having the backtrace print the value which
+ was passed in, and "print foo" print the value as modified
+ within the called function, makes perfect sense to me.
+
+ Additional note: It might be nice if "info args" displayed
+ both values.
+ One more note: There is a case with sparc structure passing
+ where we need to use the LOC_REGISTER, but this is dealt with
+ by creating a single LOC_REGPARM in symbol reading. */
+
+ /* Leave sym (the LOC_ARG) alone. */
+ ;
+ }
+ else
+ sym = nsym;
+ }