RFC: fix PR symtab/11464

[Tom Tromey <tromey@redhat.com>]

This patch fixes PR symtab/11464.

The bug is that using a quoted destructor in an expression crashes gdb.
The example from the PR is: ptype gnu_obj_1::'~gnu_obj_1'
This is odd, but of course shouldn't crash.

The basic problem was that when yylex and classify_inner_name were
updated to handle NAME in addition to TYPENAME, nothing was done to
ensure that the value of yylval seen by classify_inner_name actually had
a valid 'tsym.type' field.  And, in this case, it doesn't.

The patch fixes this by making some state more explicit.  I think this
is a plus -- really the whole lexer could use a cleanup along these
lines, removing most uses of yylval, ensuring that the proper union
fields are always used, etc.  But, I didn't go that far.

Built and regtested on x86-64 Fedora 16.
A new test case, from the PR, is included -- I didn't include the full
patch from the PR as it also covers a couple of unrelated bugs.

Tom

2013-01-10  Tom Tromey  <tromey@redhat.com>

	PR symtab/11464:
	* c-exp.y (lex_one_token): Initialize other fields of yylval on
	NAME return.
	(classify_inner_name): Remove 'first_name' argument, add
	'context'.  Remove unused variable.
	(yylex): Explicitly maintain the context type.  Exit loop earlier
	if NAME result is seen.

2013-01-10  Tom Tromey  <tromey@redhat.com>

	* gdb.cp/m-static.cc (gnu_obj_1::~gnu_obj_1): New destructor.
	* gdb.cp/m-static.exp: Add tests to print quoted destructor.

diff --git a/gdb/c-exp.y b/gdb/c-exp.y
index 9847120..9ef4b39 100644
--- a/gdb/c-exp.y
+++ b/gdb/c-exp.y
@@ -2719,6 +2719,10 @@ lex_one_token (void)
 
   if (parse_completion && *lexptr == '\0')
     saw_name_at_eof = 1;
+
+  yylval.ssym.stoken = yylval.sval;
+  yylval.ssym.sym = NULL;
+  yylval.ssym.is_a_field_of_this = 0;
   return NAME;
 }
 
@@ -2859,26 +2863,26 @@ classify_name (const struct block *block)
 }
 
 /* Like classify_name, but used by the inner loop of the lexer, when a
-   name might have already been seen.  FIRST_NAME is true if the token
-   in `yylval' is the first component of a name, false otherwise.  */
+   name might have already been seen.  CONTEXT is the context type, or
+   NULL if this is the first component of a name.  */
 
 static int
-classify_inner_name (const struct block *block, int first_name)
+classify_inner_name (const struct block *block, struct type *context)
 {
-  struct type *type, *new_type;
+  struct type *type;
   char *copy;
 
-  if (first_name)
+  if (context == NULL)
     return classify_name (block);
 
-  type = check_typedef (yylval.tsym.type);
+  type = check_typedef (context);
   if (TYPE_CODE (type) != TYPE_CODE_STRUCT
       && TYPE_CODE (type) != TYPE_CODE_UNION
       && TYPE_CODE (type) != TYPE_CODE_NAMESPACE)
     return ERROR;
 
-  copy = copy_name (yylval.tsym.stoken);
-  yylval.ssym.sym = cp_lookup_nested_symbol (yylval.tsym.type, copy, block);
+  copy = copy_name (yylval.ssym.stoken);
+  yylval.ssym.sym = cp_lookup_nested_symbol (type, copy, block);
   if (yylval.ssym.sym == NULL)
     return ERROR;
 
@@ -2893,7 +2897,6 @@ classify_inner_name (const struct block *block, int first_name)
       return TYPENAME;
 
     default:
-      yylval.ssym.is_a_field_of_this = 0;
       return NAME;
     }
   internal_error (__FILE__, __LINE__, _("not reached"));
@@ -2915,6 +2918,7 @@ yylex (void)
 {
   token_and_value current;
   int first_was_coloncolon, last_was_coloncolon, first_iter;
+  struct type *context_type = NULL;
 
   if (popping && !VEC_empty (token_and_value, token_fifo))
     {
@@ -2936,7 +2940,10 @@ yylex (void)
   last_was_coloncolon = first_was_coloncolon;
   obstack_free (&name_obstack, obstack_base (&name_obstack));
   if (!last_was_coloncolon)
-    obstack_grow (&name_obstack, yylval.sval.ptr, yylval.sval.length);
+    {
+      obstack_grow (&name_obstack, yylval.sval.ptr, yylval.sval.length);
+      context_type = yylval.tsym.type;
+    }
   current.value = yylval;
   first_iter = 1;
   while (1)
@@ -2953,7 +2960,7 @@ yylex (void)
 	  classification = classify_inner_name (first_was_coloncolon
 						? NULL
 						: expression_context_block,
-						first_iter);
+						context_type);
 	  /* We keep going until we either run out of names, or until
 	     we have a qualified name which is not a type.  */
 	  if (classification != TYPENAME && classification != NAME)
@@ -2964,7 +2971,7 @@ yylex (void)
 	    }
 
 	  /* Update the partial name we are constructing.  */
-	  if (!first_iter)
+	  if (context_type != NULL)
 	    {
 	      /* We don't want to put a leading "::" into the name.  */
 	      obstack_grow_str (&name_obstack, "::");
@@ -2978,6 +2985,11 @@ yylex (void)
 	  current.token = classification;
 
 	  last_was_coloncolon = 0;
+	  
+	  if (classification == NAME)
+	    break;
+
+	  context_type = yylval.tsym.type;
 	}
       else if (next.token == COLONCOLON && !last_was_coloncolon)
 	last_was_coloncolon = 1;
diff --git a/gdb/testsuite/gdb.cp/m-static.cc b/gdb/testsuite/gdb.cp/m-static.cc
index e9dce18..8472988 100644
--- a/gdb/testsuite/gdb.cp/m-static.cc
+++ b/gdb/testsuite/gdb.cp/m-static.cc
@@ -17,6 +17,7 @@ protected:
 
 public:
   gnu_obj_1(antiquities a, long l) {}
+  ~gnu_obj_1() {}
 
   long method ()
   {
diff --git a/gdb/testsuite/gdb.cp/m-static.exp b/gdb/testsuite/gdb.cp/m-static.exp
index 38d2498..ae4b2ad 100644
--- a/gdb/testsuite/gdb.cp/m-static.exp
+++ b/gdb/testsuite/gdb.cp/m-static.exp
@@ -64,6 +64,14 @@ gdb_test "print test1.key2" "\\$\[0-9\]* = 77" "simple object, static long"
 # simple object, static enum
 gdb_test "print test1.value" "\\$\[0-9\]* = oriental" "simple object, static enum"
 
+gdb_test "print test1.'~gnu_obj_1'" \
+    { = {void \(gnu_obj_1 \*( const)?, int\)} 0x[0-9a-f]+ <gnu_obj_1::~gnu_obj_1\(\)>} \
+    "simple object instance, print quoted destructor"
+
+gdb_test "ptype gnu_obj_1::'~gnu_obj_1'" \
+    {type = void \(gnu_obj_1 \* const\)} \
+    "simple object class, ptype quoted destructor"
+
 # Two.
 
 # derived template object, base static const bool