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Re: PATCH: revive function address warning
Ben Elliston <bje@au1.ibm.com> writes:
>> Ben proposed -Walways-true and I believe he is implementing that.
>> This warning is in the same category as those we have for
>
> How's this? Tested with a bootstrap and regression test run on
> powerpc-linux.
>
> 2005-12-09 Ben Elliston <bje@au.ibm.com>
>
> * c-common.c (c_common_truthvalue_conversion): Generalise warning
> for addresses converted to booleans; not just function addresses.
> * c-typeck.c (build_binary_op): Warn for address comparisons which
> can never be NULL (eg. func == NULL or &var == NULL).
> * common.opt (Walways-true): New option.
> * c-opts.c (c_common_handle_option): Set it with -Wall.
> * doc/invoke.texi: Document it.
>
> testsuite/
> 2005-12-09 Ben Elliston <bje@au.ibm.com>
>
> * gcc.dg/warn-addr-cmp.c: New test.
>
> Index: doc/invoke.texi
> ===================================================================
> --- doc/invoke.texi (revision 108457)
> +++ doc/invoke.texi (working copy)
> @@ -222,7 +222,7 @@
> @item Warning Options
> @xref{Warning Options,,Options to Request or Suppress Warnings}.
> @gccoptlist{-fsyntax-only -pedantic -pedantic-errors @gol
> --w -Wextra -Wall -Waggregate-return -Wno-attributes @gol
> +-w -Wextra -Wall -Waggregate-return -Walways-true -Wno-attributes @gol
> -Wc++-compat -Wcast-align -Wcast-qual -Wchar-subscripts -Wcomment @gol
> -Wconversion -Wno-deprecated-declarations @gol
> -Wdisabled-optimization -Wno-div-by-zero -Wno-endif-labels @gol
> @@ -3112,6 +3112,11 @@
> called. (In languages where you can return an array, this also elicits
> a warning.)
>
> +@item -Walways-true
> +@opindex Walways-true
> +Warn about comparisons which are always true such as testing if unsigned
> +values are greater than zero.
> +
Should this be 'greater than or equal to'?
--
Thanks,
Jim
http://www.csclub.uwaterloo.ca/~ja2morri/
http://phython.blogspot.com
http://open.nit.ca/wiki/?page=jim