iconv/loop.c vs gcc-3.1: divide by zero in #if

iconv/loop.c vs gcc-3.1: divide by zero in #if

[Roland McGrath]

Using gcc-3.1 I get "divide by zero in #if" for several iconv modules
without the following change.  Ok to put this in (with log entry, of course)?


Index: loop.c
===================================================================
RCS file: /cvs/glibc/libc/iconv/loop.c,v
retrieving revision 1.28
diff -u -p -r1.28 loop.c
--- loop.c	15 Jul 2001 15:18:22 -0000	1.28
+++ loop.c	16 May 2002 06:24:49 -0000
@@ -1,5 +1,5 @@
 /* Conversion loop frame work.
-   Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
+   Copyright (C) 1998,99,2000,01,02 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
 
@@ -296,17 +296,19 @@ FCTNAME (LOOPFCT) (struct __gconv_step *
 /* Include the file a second time to define the function to handle
    unaligned access.  */
 #if !defined DEFINE_UNALIGNED && !defined _STRING_ARCH_unaligned \
-    && MIN_NEEDED_FROM != 1 && MAX_NEEDED_FROM % MIN_NEEDED_FROM == 0 \
-    && MIN_NEEDED_TO != 1 && MAX_NEEDED_TO % MIN_NEEDED_TO == 0
-# undef get16
-# undef get32
-# undef put16
-# undef put32
-# undef unaligned
-
-# define DEFINE_UNALIGNED
-# include "loop.c"
-# undef DEFINE_UNALIGNED
+    && MIN_NEEDED_FROM > 1 && MIN_NEEDED_TO > 1
+# if MAX_NEEDED_FROM % MIN_NEEDED_FROM == 0 \
+#   && MAX_NEEDED_TO % MIN_NEEDED_TO == 0
+#  undef get16
+#  undef get32
+#  undef put16
+#  undef put32
+#  undef unaligned
+
+#  define DEFINE_UNALIGNED
+#  include "loop.c"
+#  undef DEFINE_UNALIGNED
+# endif
 #endif
 
 

Re: iconv/loop.c vs gcc-3.1: divide by zero in #if

[Andreas Jaeger]

Roland McGrath <roland@frob.com> writes:

> Using gcc-3.1 I get "divide by zero in #if" for several iconv modules
> without the following change.  Ok to put this in (with log entry, of course)?

This just bits me also.  Roland's patch (with the obvious fix) solved
the problem.

I'd like to see this committed soon. 

>
> Index: loop.c
> ===================================================================
> RCS file: /cvs/glibc/libc/iconv/loop.c,v
> retrieving revision 1.28
> diff -u -p -r1.28 loop.c
> --- loop.c	15 Jul 2001 15:18:22 -0000	1.28
> +++ loop.c	16 May 2002 06:24:49 -0000
> @@ -1,5 +1,5 @@
>  /* Conversion loop frame work.
> -   Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
> +   Copyright (C) 1998,99,2000,01,02 Free Software Foundation, Inc.
>     This file is part of the GNU C Library.
>     Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
>  
> @@ -296,17 +296,19 @@ FCTNAME (LOOPFCT) (struct __gconv_step *
>  /* Include the file a second time to define the function to handle
>     unaligned access.  */
>  #if !defined DEFINE_UNALIGNED && !defined _STRING_ARCH_unaligned \
> -    && MIN_NEEDED_FROM != 1 && MAX_NEEDED_FROM % MIN_NEEDED_FROM == 0 \
> -    && MIN_NEEDED_TO != 1 && MAX_NEEDED_TO % MIN_NEEDED_TO == 0
> -# undef get16
> -# undef get32
> -# undef put16
> -# undef put32
> -# undef unaligned
> -
> -# define DEFINE_UNALIGNED
> -# include "loop.c"
> -# undef DEFINE_UNALIGNED
> +    && MIN_NEEDED_FROM > 1 && MIN_NEEDED_TO > 1
> +# if MAX_NEEDED_FROM % MIN_NEEDED_FROM == 0 \
> +#   && MAX_NEEDED_TO % MIN_NEEDED_TO == 0

Remove the hash here,

Andreas

> +#  undef get16
> +#  undef get32
> +#  undef put16
> +#  undef put32
> +#  undef unaligned
> +
> +#  define DEFINE_UNALIGNED
> +#  include "loop.c"
> +#  undef DEFINE_UNALIGNED
> +# endif
>  #endif
>  
>  
>

-- 
 Andreas Jaeger
  SuSE Labs aj@suse.de
   private aj@arthur.inka.de
    http://www.suse.de/~aj