Re: break jmisc.main

[Daniel Jacobowitz <drow@mvista.com>]

On Thu, Mar 13, 2003 at 03:32:27PM -0800, David Carlton wrote:
> On 13 Mar 2003 13:15:59 -0800, David Carlton <carlton@math.stanford.edu> said:
> 
> > I'll think about this, but if there's no easy way to get a good
> > guess at the current language when building minimal symbol tables, I
> > suppose I'll reluctantly take a stab at the temporary solution.
> 
> Actually, it wasn't so bad: Daniel did a good job of making the new
> symbol name initialization functions modular, so I only had to touch
> one of them.  Here's a patch that might work; it doesn't cause any
> non-Java regressions, but this machine doesn't have gcj 3.2 on it, so
> I have no idea if it actually fixes the problem.  I'll try to test it
> tonight when I get home, but if anybody reading this wants to test it
> before then, that would be great.  The symtab.h part is purely
> cosmetic: just apply the symtab.c part, if you don't want to have to
> recompile every file that depends on symtab.h.

Hmm, I like this in principle.  Could it have a more prominent FIXME on
it though?  It's really not a good long term solution.  We shouldn't
need both demangled copies... or if we do, then perhaps both should be
associated with the minsym.

> 
> David Carlton
> carlton@math.stanford.edu
> 
> 2003-03-13  David Carlton  <carlton@math.stanford.edu>
> 
> 	* symtab.c (symbol_set_names): Add prefix when storing Java names
> 	in hash table.  Fix for PR java/1039.
> 	* symtab.h: Change 'name' argument in declaration of
> 	symbol_set_names to 'linkage_name'.
> 	(SYMBOL_SET_NAMES): Change 'name' argument to 'linkage_name'.
> 
> Index: symtab.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/symtab.c,v
> retrieving revision 1.99
> diff -u -p -r1.99 symtab.c
> --- symtab.c	4 Mar 2003 17:06:21 -0000	1.99
> +++ symtab.c	13 Mar 2003 22:59:00 -0000
> @@ -484,61 +484,103 @@ symbol_find_demangled_name (struct gener
>    return NULL;
>  }
>  
> -/* Set both the mangled and demangled (if any) names for GSYMBOL based on
> -   NAME and LEN.  The hash table corresponding to OBJFILE is used, and the
> -   memory comes from that objfile's symbol_obstack.  NAME is copied, so the
> -   pointer can be discarded after calling this function.  */
> +/* Set both the mangled and demangled (if any) names for GSYMBOL based
> +   on LINKAGE_NAME and LEN.  The hash table corresponding to OBJFILE
> +   is used, and the memory comes from that objfile's symbol_obstack.
> +   LINKAGE_NAME is copied, so the pointer can be discarded after
> +   calling this function.  */
> +
> +/* We have to be careful when dealing with Java names: when we run
> +   into a Java minimal symbol, we don't know it's a Java symbol, so it
> +   gets demangled as a C++ name.  This is unfortunate, but there's not
> +   much we can do about it: but when demangling partial symbols and
> +   regular symbols, we'd better not reuse the wrong demangled name.
> +   (See PR gdb/1039.)  We solve this by putting a distinctive prefix
> +   on Java names when storing them in the hash table.  */
> +
> +#define JAVA_PREFIX "##JAVA$$"
> +#define JAVA_PREFIX_LEN 8
>  
>  void
>  symbol_set_names (struct general_symbol_info *gsymbol,
> -		  const char *name, int len, struct objfile *objfile)
> +		  const char *linkage_name, int len, struct objfile *objfile)
>  {
>    char **slot;
> -  const char *tmpname;
> +  /* A 0-terminated copy of the linkage name.  */
> +  const char *linkage_name_copy;
> +  /* A copy of the linkage name that might have a special Java prefix
> +     added to it, for use when looking names up in the hash table.  */
> +  const char *lookup_name;
> +  /* The length of lookup_name.  */
> +  int lookup_len;
>  
>    if (objfile->demangled_names_hash == NULL)
>      create_demangled_names_hash (objfile);
>  
> -  /* The stabs reader generally provides names that are not NULL-terminated;
> -     most of the other readers don't do this, so we can just use the given
> -     copy.  */
> -  if (name[len] != 0)
> +  /* The stabs reader generally provides names that are not
> +     NUL-terminated; most of the other readers don't do this, so we
> +     can just use the given copy, unless we're in the Java case.  */
> +  if (gsymbol->language == language_java)
>      {
> -      char *alloc_name = alloca (len + 1);
> -      memcpy (alloc_name, name, len);
> -      alloc_name[len] = 0;
> -      tmpname = alloc_name;
> +      char *alloc_name;
> +      lookup_len = len + JAVA_PREFIX_LEN;
> +
> +      alloc_name = alloca (lookup_len + 1);
> +      memcpy (alloc_name, JAVA_PREFIX, JAVA_PREFIX_LEN);
> +      memcpy (alloc_name + JAVA_PREFIX_LEN, linkage_name, len);
> +      alloc_name[lookup_len] = '\0';
> +
> +      lookup_name = alloc_name;
> +      linkage_name_copy = alloc_name + JAVA_PREFIX_LEN;
> +    }
> +  else if (linkage_name[len] != '\0')
> +    {
> +      char *alloc_name;
> +      lookup_len = len;
> +
> +      alloc_name = alloca (lookup_len + 1);
> +      memcpy (alloc_name, linkage_name, len);
> +      alloc_name[lookup_len] = '\0';
> +
> +      lookup_name = alloc_name;
> +      linkage_name_copy = alloc_name;
>      }
>    else
> -    tmpname = name;
> +    {
> +      lookup_len = len;
> +      lookup_name = linkage_name;
> +      linkage_name_copy = linkage_name;
> +    }
>  
> -  slot = (char **) htab_find_slot (objfile->demangled_names_hash, tmpname, INSERT);
> +  slot = (char **) htab_find_slot (objfile->demangled_names_hash,
> +				   lookup_name, INSERT);
>  
>    /* If this name is not in the hash table, add it.  */
>    if (*slot == NULL)
>      {
> -      char *demangled_name = symbol_find_demangled_name (gsymbol, tmpname);
> +      char *demangled_name = symbol_find_demangled_name (gsymbol,
> +							 linkage_name_copy);
>        int demangled_len = demangled_name ? strlen (demangled_name) : 0;
>  
>        /* If there is a demangled name, place it right after the mangled name.
>  	 Otherwise, just place a second zero byte after the end of the mangled
>  	 name.  */
>        *slot = obstack_alloc (&objfile->symbol_obstack,
> -			     len + demangled_len + 2);
> -      memcpy (*slot, tmpname, len + 1);
> -      if (demangled_name)
> +			     lookup_len + demangled_len + 2);
> +      memcpy (*slot, lookup_name, lookup_len + 1);
> +      if (demangled_name != NULL)
>  	{
> -	  memcpy (*slot + len + 1, demangled_name, demangled_len + 1);
> +	  memcpy (*slot + lookup_len + 1, demangled_name, demangled_len + 1);
>  	  xfree (demangled_name);
>  	}
>        else
> -	(*slot)[len + 1] = 0;
> +	(*slot)[lookup_len + 1] = '\0';
>      }
>  
> -  gsymbol->name = *slot;
> -  if ((*slot)[len + 1])
> +  gsymbol->name = *slot + lookup_len - len;
> +  if ((*slot)[lookup_len + 1] != '\0')
>      gsymbol->language_specific.cplus_specific.demangled_name
> -      = &(*slot)[len + 1];
> +      = &(*slot)[lookup_len + 1];
>    else
>      gsymbol->language_specific.cplus_specific.demangled_name = NULL;
>  }
> Index: symtab.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/symtab.h,v
> retrieving revision 1.65
> diff -u -p -r1.65 symtab.h
> --- symtab.h	3 Mar 2003 18:34:12 -0000	1.65
> +++ symtab.h	13 Mar 2003 22:59:05 -0000
> @@ -156,10 +156,10 @@ extern void symbol_init_language_specifi
>  extern void symbol_init_demangled_name (struct general_symbol_info *symbol,
>  					struct obstack *obstack);
>  
> -#define SYMBOL_SET_NAMES(symbol,name,len,objfile) \
> -  symbol_set_names (&(symbol)->ginfo, name, len, objfile)
> +#define SYMBOL_SET_NAMES(symbol,linkage_name,len,objfile) \
> +  symbol_set_names (&(symbol)->ginfo, linkage_name, len, objfile)
>  extern void symbol_set_names (struct general_symbol_info *symbol,
> -			      const char *name, int len,
> +			      const char *linkage_name, int len,
>  			      struct objfile *objfile);
>  
>  /* Now come lots of name accessor macros.  Short version as to when to
> 

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer