diff --git a/parse.y b/parse.y
index 83d5b9f..5e3ccde 100644
--- a/parse.y
+++ b/parse.y
@@ -2288,30 +2288,7 @@ shell_getc (remove_quoted_newline)
 	      continue;
 	    }
 
-	  /* Theoretical overflow */
-	  /* If we can't put 256 bytes more into the buffer, allocate
-	     everything we can and fill it as full as we can. */
-	  /* XXX - we ignore rest of line using `truncating' flag */
-	  if (shell_input_line_size > (SIZE_MAX - 256))
-	    {
-	      size_t n;
-
-	      n = SIZE_MAX - i;	/* how much more can we put into the buffer? */
-	      if (n <= 2)	/* we have to save 1 for the newline added below */
-		{
-		  if (truncating == 0)
-		    internal_warning("shell_getc: shell_input_line_size (%zu) exceeds SIZE_MAX (%llu): line truncated", shell_input_line_size, SIZE_MAX);
-		  shell_input_line[i] = '\0';
-		  truncating = 1;
-		}
-	      if (shell_input_line_size < SIZE_MAX)
-		{
-		  shell_input_line_size = SIZE_MAX;
-		  shell_input_line = xrealloc (shell_input_line, shell_input_line_size);
-		}
-	    }
-	  else
-	    RESIZE_MALLOCED_BUFFER (shell_input_line, i, 2, shell_input_line_size, 256);
+	  RESIZE_MALLOCED_BUFFER (shell_input_line, i, 2, shell_input_line_size, 256);
 
 	  if (c == EOF)
 	    {
@@ -2424,7 +2401,7 @@ shell_getc (remove_quoted_newline)
 	 not already end in an EOF character.  */
       if (shell_input_line_terminator != EOF)
 	{
-	  if (shell_input_line_size < SIZE_MAX && shell_input_line_len > shell_input_line_size - 3)
+	  if (shell_input_line_len + 3 > shell_input_line_size)
 	    shell_input_line = (char *)xrealloc (shell_input_line,
 					1 + (shell_input_line_size += 2));