cppexp.c (lex): Use %.*s to print non-NUL-terminated string.

	* cppexp.c (lex): Use %.*s to print non-NUL-terminated string.
	Make error message friendlier.

From-SVN: r33829

gcc/ChangeLog

 2000-05-10  Zack Weinberg  <zack@wolery.cumb.org>
 
+	* cppexp.c (lex): Use %.*s to print non-NUL-terminated string.
+	Make error message friendlier.
+
 	* cpphash.h (struct hashnode): Use struct hack for name
 	member.
 	* cpphash.c (struct hashdummy): New.

gcc/cppexp.c

@@ -466,8 +466,8 @@ lex (pfile, skip_evaluation)
 		&& tok_start[1] == toktab->operator[1])
 		break;
 	  if (toktab->token == ERROR)
-	    cpp_error (pfile, "'%s' not allowed in operand of #if",
-		       tok_start);
+	    cpp_error (pfile, "'%.*s' is not allowed in #if expressions",
+		       (int) (tok_end - tok_start), tok_start);
 	  op.op = toktab->token; 
 	  return op;
 	}

gcc/testsuite/gcc.dg/cpp-if4.c

+/* Regression test for proper error message.  The token name isn't
+   NUL terminated, so we would print garbage after it.  */
+/* { dg-do compile } */
+
+#if 1 += 2   /* { dg-error "'\\+=' is not allowed" "+= in if" } */
+syntax_error
+#endif
+int foo;