* value.h (struct value): Add modifiable field.

	* values.c (allocate_value, record_latest_value, value_copy): Set it.
	(record_latest_value): Don't mess with VALUE_LVAL of value.
	* valops.c (value_assign): Check it.  Reword existing error
	message on not_lval.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c6e5b11c64a3635d45d2f2b41a9648d3360fd278..2d2b7bd6360d66408c2ef3a8dc980af1b51b12de 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,11 @@
 Mon Feb 28 12:40:46 1994  Jim Kingdon  (kingdon@deneb.cygnus.com)
 
+       * value.h (struct value): Add modifiable field.
+       * values.c (allocate_value, record_latest_value, value_copy): Set it.
+       (record_latest_value): Don't mess with VALUE_LVAL of value.
+       * valops.c (value_assign): Check it.  Reword existing error
+       message on not_lval.
+
        * mips-tdep.c (mips_step_skips_delay), config/mips/tm-mips.h
        (STEP_SKIPS_DELAY): Added.
        * infrun.c (proceed) [STEP_SKIPS_DELAY]: Check for a breakpoint in

diff --git a/gdb/valops.c b/gdb/valops.c
index 8a7b8d82172b581e6e044f5e061082ba7c3c9bcb..24f2c780f59ad5c263a5bf05c207be43896f8d04 100644 (file)
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -289,6 +289,9 @@ value_assign (toval, fromval)
   char raw_buffer[MAX_REGISTER_RAW_SIZE];
   int use_buffer = 0;
 
+  if (!toval->modifiable)
+    error ("Left operand of assignment is not a modifiable lvalue.");
+
   COERCE_ARRAY (fromval);
   COERCE_REF (toval);
 
@@ -488,7 +491,7 @@ Can't handle bitfield which doesn't fit in a single register.");
        
 
     default:
-      error ("Left side of = operation is not an lvalue.");
+      error ("Left operand of assignment is not an lvalue.");
     }
 
   /* Return a value just like TOVAL except with the contents of FROMVAL
@@ -1101,6 +1104,7 @@ call_function_by_hand (function, nargs, args)
        char format[80];
        sprintf (format, "at %s", local_hex_format ());
        name = alloca (80);
+       /* FIXME-32x64: assumes funaddr fits in a long.  */
        sprintf (name, format, (unsigned long) funaddr);
       }
 

diff --git a/gdb/value.h b/gdb/value.h
index dbc0f863310e1e449f9eff4617e540c667b4926d..87ead1be0ef1495ce4a2ac4b36e31cee1c1649a7 100644 (file)
--- a/gdb/value.h
+++ b/gdb/value.h
@@ -1,5 +1,5 @@
 /* Definitions for values of C expressions, for GDB.
-   Copyright 1986, 1987, 1989, 1992 Free Software Foundation, Inc.
+   Copyright 1986, 1987, 1989, 1992, 1993, 1994 Free Software Foundation, Inc.
 
 This file is part of GDB.
 
@@ -47,6 +47,8 @@ struct value
     /* Type of value; either not an lval, or one of the various
        different possible kinds of lval.  */
     enum lval_type lval;
+    /* Is it modifiable?  Only relevant if lval != not_lval.  */
+    int modifiable;
     /* Location of value (if lval).  */
     union
       {
@@ -102,9 +104,7 @@ struct value
     union {
       long contents[1];
       double force_double_align;
-#ifdef CC_HAS_LONG_LONG
-      long long force_longlong_align;
-#endif
+      LONGEST force_longlong_align;
     } aligner;
 
   };
@@ -200,7 +200,7 @@ struct fn_field;
 #endif
 
 extern void
-print_address_demangle PARAMS ((CORE_ADDR, FILE *, int));
+print_address_demangle PARAMS ((CORE_ADDR, GDB_FILE *, int));
 
 extern LONGEST
 value_as_long PARAMS ((value val));
@@ -238,6 +238,8 @@ extern value value_of_variable PARAMS ((struct symbol *var, struct block *b));
 
 extern value value_of_register PARAMS ((int regnum));
 
+extern int symbol_read_needs_frame PARAMS ((struct symbol *));
+
 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 extern value read_var_value PARAMS ((struct symbol *var,
                                     struct frame_info *frame));
@@ -310,6 +312,10 @@ extern value value_being_returned PARAMS ((struct type *valtype,
                                           char retbuf[REGISTER_BYTES],
                                           int struct_return));
 
+extern value value_in PARAMS ((value element, value set));
+
+extern int value_bit_index PARAMS ((struct type *type, char *addr, int index));
+
 extern int
 using_struct_return PARAMS ((value function, CORE_ADDR funcaddr,
                             struct type *value_type, int gcc_p));
@@ -420,7 +426,7 @@ extern CORE_ADDR
 read_register PARAMS ((int regno));
 
 extern void
-write_register PARAMS ((int regno, long val));
+write_register PARAMS ((int regno, LONGEST val));
 
 extern void
 supply_register PARAMS ((int regno, char *val));
@@ -435,7 +441,7 @@ extern void
 modify_field PARAMS ((char *addr, LONGEST fieldval, int bitpos, int bitsize));
 
 extern void
-type_print PARAMS ((struct type *type, char *varstring, FILE *stream,
+type_print PARAMS ((struct type *type, char *varstring, GDB_FILE *stream,
                    int show));
 
 extern char *
@@ -443,28 +449,28 @@ baseclass_addr PARAMS ((struct type *type, int index, char *valaddr,
                        value *valuep, int *errp));
 
 extern void
-print_longest PARAMS ((FILE *stream, int format, int use_local,
-                      LONGEST value));
+print_longest PARAMS ((GDB_FILE *stream, int format, int use_local,
+                      LONGEST val));
 
 extern void
-print_floating PARAMS ((char *valaddr, struct type *type, FILE *stream));
+print_floating PARAMS ((char *valaddr, struct type *type, GDB_FILE *stream));
 
 extern int
-value_print PARAMS ((value val, FILE *stream, int format,
+value_print PARAMS ((value val, GDB_FILE *stream, int format,
                     enum val_prettyprint pretty));
 
 extern int
 val_print PARAMS ((struct type *type, char *valaddr, CORE_ADDR address,
-                  FILE *stream, int format, int deref_ref,
+                  GDB_FILE *stream, int format, int deref_ref,
                   int recurse, enum val_prettyprint pretty));
 
 extern int
-val_print_string PARAMS ((CORE_ADDR addr, unsigned int len, FILE *stream));
+val_print_string PARAMS ((CORE_ADDR addr, unsigned int len, GDB_FILE *stream));
 
 /* FIXME:  Assumes equivalence of "struct frame_info *" and "FRAME" */
 extern void
 print_variable_value PARAMS ((struct symbol *var, struct frame_info *frame,
-                             FILE *stream));
+                             GDB_FILE *stream));
 
 extern value
 value_arg_coerce PARAMS ((value));
@@ -473,7 +479,7 @@ extern int
 check_field PARAMS ((value, const char *));
 
 extern void
-c_typedef_print PARAMS ((struct type *type, struct symbol *new, FILE *stream));
+c_typedef_print PARAMS ((struct type *type, struct symbol *new, GDB_FILE *stream));
 
 extern char *
 internalvar_name PARAMS ((struct internalvar *var));

diff --git a/gdb/values.c b/gdb/values.c
index 451cf51e962db7d34b24abee252d99250db7c8b7..34ea2d191f7c0e20552d87e4ffacfc3c390f7647 100644 (file)
--- a/gdb/values.c
+++ b/gdb/values.c
@@ -91,6 +91,7 @@ allocate_value (type)
   VALUE_REGNO (val) = -1;
   VALUE_LAZY (val) = 0;
   VALUE_OPTIMIZED_OUT (val) = 0;
+  val->modifiable = 1;
   return val;
 }
 
@@ -210,6 +211,7 @@ value_copy (arg)
   VALUE_BITSIZE (val) = VALUE_BITSIZE (arg);
   VALUE_REGNO (val) = VALUE_REGNO (arg);
   VALUE_LAZY (val) = VALUE_LAZY (arg);
+  val->modifiable = arg->modifiable;
   if (!VALUE_LAZY (val))
     {
       memcpy (VALUE_CONTENTS_RAW (val), VALUE_CONTENTS_RAW (arg),
@@ -262,7 +264,10 @@ record_latest_value (val)
      a value on the value history never changes.  */
   if (VALUE_LAZY (val))
     value_fetch_lazy (val);
-  VALUE_LVAL (val) = not_lval;
+  /* We preserve VALUE_LVAL so that the user can find out where it was fetched
+     from.  This is a bit dubious, because then *&$1 does not just return $1
+     but the current contents of that location.  c'est la vie...  */
+  val->modifiable = 0;
   release_value (val);
 
   /* Now we regard value_history_count as origin-one