3279,3280c3279
< Since @option{-Wformat} also checks for null format arguments for
< several functions, @option{-Wformat} also implies @option{-Wnonnull}.
---
> @option{-Wformat} implies the following options:
3282,3286c3281,3287
< @option{-Wformat} is included in @option{-Wall}.  For more control over some
< aspects of format checking, the options @option{-Wformat-y2k},
< @option{-Wno-format-extra-args}, @option{-Wno-format-zero-length},
< @option{-Wformat-nonliteral}, @option{-Wformat-security}, and
< @option{-Wformat=2} are available, but are not included in @option{-Wall}.
---
> @gccoptlist{-Wformat-contains-nul   @gol
> -Wformat-extra-args  @gol
> -Wformat-zero-length  @gol
> -Wnon-null  @gol
> }
> 
> @option{-Wformat} is included in @option{-Wall}.
3292,3293c3293
< @option{-Wformat}.  Currently equivalent to @option{-Wformat
< -Wformat-nonliteral -Wformat-security -Wformat-y2k}.
---
> @option{-Wformat}.  Currently equivalent to:
3295,3296c3295,3301
< @item -Wno-format-contains-nul
< @opindex Wno-format-contains-nul
---
> @gccoptlist{-Wformat  @gol
> -Wformat-non-literal  @gol
> -Wformat-security  @gol
> -Wformat-y2k  @gol
> }
> 
> @item -Wformat-contains-nul
3298,3299c3303,3304
< If @option{-Wformat} is specified, do not warn about format strings that
< contain NUL bytes.
---
> @opindex Wno-format-contains-nul
> Warn about format strings that contain NUL bytes.
3301,3302c3306
< @item -Wno-format-extra-args
< @opindex Wno-format-extra-args
---
> @item -Wformat-extra-args
3304,3306c3308,3310
< If @option{-Wformat} is specified, do not warn about excess arguments to a
< @code{printf} or @code{scanf} format function.  The C standard specifies
< that such arguments are ignored.
---
> @opindex Wno-format-extra-args
> Warn about excess arguments to a @code{printf} or @code{scanf} format function.
> The C standard specifies that such arguments are ignored.
3311,3314c3315,3318
< type to pass to @code{va_arg} to skip the unused arguments.  However,
< in the case of @code{scanf} formats, this option suppresses the
< warning if the unused arguments are all pointers, since the Single
< Unix Specification says that such unused arguments are allowed.
---
> type to pass to @code{va_arg} to skip the unused arguments.  In the case of
> @code{scanf} formats, this option gives a warning if the unused
> arguments are all pointers. The Single Unix Specification says that such
> unused arguments are allowed.
3316,3317c3320
< @item -Wno-format-zero-length
< @opindex Wno-format-zero-length
---
> @item -Wformat-zero-length
3319,3320c3322,3323
< If @option{-Wformat} is specified, do not warn about zero-length formats.
< The C standard specifies that zero-length formats are allowed.
---
> @opindex Wno-format-zero-length
> Warn about zero-length formats. The C standard specifies that zero-length formats are allowed.