Re: [BUG] coding.c/decode_coding_iso2022

[Kenichi Handa]

In article <address@hidden>, David Abrahams <address@hidden> writes:
> Tired of the numerous crashes I've been getting under NT, I
> recompiled emacs with all the runtime checks enabled.  I think I'll
> be posting lots of reports.

> The title function uses variable c2 uninitialized during this phase
> of the make process:

>    Loading language/devanagari (source)...

> The stack trace is:

>       ntdll.dll!77f75a58()    
>       temacs.exe!failwithmessage(void * retaddr=0x011b5c7f, int 
> crttype=0x00000001, int errnum=0x00000003, const char * msg=0x0111431e)  + 
> 0x106      C++
>       temacs.exe!_RTC_UninitUse(const char * varname=0x01114900)  + 0x9c      
> C++
>>      temacs.exe!decode_coding_iso2022()  Line 2169 + 0x33c   C

It seems that the relevant line is this:

      c = DECODE_ISO_CHARACTER (charset, c1, c2);

But, ...
[...]
> Locals at the point of the error:
>       c2      0xcccccccc      int
>       c1      0x0000003b      int
> +     coding  0x0081f1e4 {type=coding_type_iso2022 eol_type=0x00000001 
> common_flags=0x00000007 ...}   coding_system *
> +     source  0x0158da80 ";;; devanagari.el --- Support for Devanagari -*- 
> coding: iso-2022-7bit; no-byte-compile: t -*-
[...]
> +     destination     0x0158d2b0 ""   unsigned char *
>       src_bytes       0x000006b7      int
>       dst_bytes       0x00000000      int
>       charset1        0xffffffff      int
>       charset 0x00000000      int
> +     src     0x0158da81 ";; devanagari.el --- Support for Devanagari -*- 
> coding: iso-2022-7bit; no-byte-compile: t -*-

[...]
>       translation_table       0x41398000      int
>       c       0xcccccccc      int
>       charset0        0x00000000      int
> +     src_end 0x0158e137 ""   unsigned char *
> +     dst_end 0x0158d2b0 ""   unsigned char *
> +     dst     0x0158d2b0 ""   unsigned char *
> +     src_base        0x0158da80 ";;; devanagari.el --- Support for 
> Devanagari -*- coding: iso-2022-7bit; no-byte-compile: t -*-

[...]
>       safe_chars      0x1137e834      int

As the value of charset is 0, c2 is never referred in the
macro DECODE_ISO_CHARACTER except for as the last argument
to the function translate_char.  And in that function also,
as charset is zero, c2 is never referred.

So, I think this is not the reason of the crash of your emacs.

---
Ken'ichi HANDA
address@hidden