Redisplay & add_control_char_runes

Here's another report from a static checker, but I'm having trouble determining whether this is one to worry about or not. In redisplay.c, take a look at create_string_text_block, starting on line 4588 of the 21.5 code. A comment near the top remarks that the buffer argument to be nil, and indeed the local variable named b (which is the corresponding struct buffer *) is checked for NULL-ness up there. I have looked carefully through this code and do not see the value of b changing anywhere. This is important, because a checker flagged a use of b waaaaaaay down on line 4998, where it gets passed to add_control_char_runes, which immediately dereferences it. So the question is this: if the buffer argument to create_string_text_block is null, is it possible to reach line 4998 and, if so, what should we do about it? -- Jerry James, Assistant Professor james(a)xemacs.org Computer Science Department http://www.cs.usu.edu/~jerry/ Utah State University