tradcif.y: Move lexptr to top of file.

* tradcif.y: Move lexptr to top of file.  Add rule to handle
        assertions in conditional expressions.
        * tradcpp.c (parse_answer): Assertions do not need to go to
        end of line in conditional directives.
        (parse_assertion): Get first character of identifiers correct.
        (test_assertion): New function.
        * tradcpp.h (test_assertion): New prototype.

From-SVN: r38011

gcc/ChangeLog

@@ -1,3 +1,13 @@
+2000-12-04  Neil Booth  <neilb@earthling.net>
+
+        * tradcif.y: Move lexptr to top of file.  Add rule to handle
+        assertions in conditional expressions.
+        * tradcpp.c (parse_answer): Assertions do not need to go to
+        end of line in conditional directives.
+        (parse_assertion): Get first character of identifiers correct.
+        (test_assertion): New function.
+        * tradcpp.h (test_assertion): New prototype.
+
 2000-12-01  Rodney Brown  <RodneyBrown@mynd.com>
 
 	* config.gcc: Fix typo for UnixWare 7.

gcc/tradcif.y

@@ -36,6 +36,11 @@ Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 
   static int expression_value;
   static jmp_buf parse_return_error;
+
+  /* During parsing of a C expression, the pointer to the next
+     character is in this variable.  */
+
+  static const char *lexptr;
 %}
 
 %union {
@@ -199,14 +204,11 @@ exp	:	exp '*' exp
 	|	NAME
 			{ $$.value = 0;
 			  $$.unsignedp = 0; }
+	|	'#'	{ $$.value =
+			    test_assertion ((unsigned char **) &lexptr); }
 	;
 %%
 
-/* During parsing of a C expression, the pointer to the next character
-   is in this variable.  */
-
-static const char *lexptr;
-
 /* Take care of parsing a number (anything that starts with a digit).
    Set yylval and return the token type; update lexptr.
    LEN is the number of characters in it.  */
@@ -389,6 +391,7 @@ yylex ()
   case '{':
   case '}':
   case ',':
+  case '#':
     lexptr++;
     return c;
     

gcc/tradcpp.c

@@ -3057,11 +3057,14 @@ parse_answer (buf, limit, answerp, type)
     buf++;
 
   /* Parentheses are optional here.  */
-  if (buf == limit && (type == T_IF || type == T_UNASSERT))
+  if (buf == limit && type == T_UNASSERT)
     return 0;
 
   if (buf == limit || *buf++ != '(')
     {
+      if (type == T_IF)
+	return 0;
+
       error ("missing '(' after predicate");
       return 1;
     }
@@ -3118,8 +3121,12 @@ parse_assertion (buf, limit, answerp, type)
   unsigned int len;
 
   bp = symname;
-  while (bp < climit && is_idchar[*bp])
-    bp++;
+  if (bp < climit && is_idstart[*bp])
+    {
+      do
+	bp++;
+      while (bp < climit && is_idchar[*bp]);
+    }
   len = bp - symname;
 
   *answerp = 0;
@@ -3130,6 +3137,8 @@ parse_assertion (buf, limit, answerp, type)
       else
 	error ("predicate must be an identifier");
     }
+  /* Unfortunately, because of the way we handle #if, we don't avoid
+     macro expansion in answers.  This is not easy to fix.  */
   else if (parse_answer (bp, climit, answerp, type) == 0)
     {
       unsigned char *sym = alloca (len + 1);
@@ -3148,6 +3157,40 @@ parse_assertion (buf, limit, answerp, type)
   return result;
 }
 
+/* Test an assertion within a preprocessor conditional.  Returns zero
+   on error or failure, one on success.  */
+int
+test_assertion (pbuf)
+     unsigned char **pbuf;	/* NUL-terminated.  */
+{
+  unsigned char *buf = *pbuf;
+  unsigned char *limit = buf + strlen ((char *) buf);
+  struct answer *answer;
+  HASHNODE *node;
+  int result = 0;
+
+  node = parse_assertion (buf, limit, &answer, T_IF);
+  if (node)
+    {
+      result = (node->type == T_ASSERT &&
+		(answer == 0 || *find_answer (node, answer) != 0));
+
+      /* Yuk.  We update pbuf to point after the assertion test.
+	 First, move past the identifier.  */
+      if (is_space[*buf])
+	buf++;
+      while (is_idchar[*buf])
+	buf++;
+      /* If we have an answer, we need to move past the parentheses.  */
+      if (answer)
+	while (*buf++ != ')')
+	  ;
+      *pbuf = buf;
+    }
+
+  return result;
+}
+
 /* Handle a #assert directive.  */
 static void
 do_assert (buf, limit, op)

gcc/tradcpp.h

@@ -34,6 +34,7 @@ extern void fancy_abort PARAMS ((int, const char *)) ATTRIBUTE_NORETURN;
 
 extern struct hashnode *lookup PARAMS ((const unsigned char *, int, int));
 extern int parse_c_expression PARAMS ((const char *));  /* in tradcif.y */
+extern int test_assertion PARAMS ((unsigned char **));
 
 /* some external tables of character types */
 extern unsigned char is_idstart[], is_idchar[];