-@c Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+@c Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
@c Free Software Foundation, Inc.
@c This is part of the GCC manual.
@c For copying conditions, see the file gcc.texi.
@code{Var} properties.
@item
+A variable record to define a variable used to store option
+information. These records have two fields: the string
+@samp{TargetVariable}, and a declaration of the type and name of the
+variable, optionally with an initializer (but without any trailing
+@samp{;}). @samp{TargetVariable} is a combination of @samp{Variable}
+and @samp{TargetSave} records in that the variable is defined in the
+@code{gcc_options} structure, but these variables are also stored in
+the @code{cl_target_option} structure. The variables are saved in the
+target save code and restored in the target restore code.
+
+@item
+A variable record to record any additional files that the
+@file{options.h} file should include. This is useful to provide
+enumeration or structure definitions needed for target variables.
+These records have two fields: the string @samp{HeaderInclude} and the
+name of the include file.
+
+@item
+A variable record to record any additional files that the
+@file{options.c} file should include. This is useful to provide
+inline functions needed for target variables and/or @code{#ifdef}
+sequences to properly set up the initialization. These records have
+two fields: the string @samp{SourceInclude} and the name of the
+include file.
+
+@item
+An enumeration record to define a set of strings that may be used as
+arguments to an option or options. These records have three fields:
+the string @samp{Enum}, a space-separated list of properties and help
+text used to describe the set of strings in @option{--help} output.
+Properties use the same format as option properties; the following are
+valid:
+@table @code
+@item Name(@var{name})
+This property is required; @var{name} must be a name (suitable for use
+in C identifiers) used to identify the set of strings in @code{Enum}
+option properties.
+
+@item Type(@var{type})
+This property is required; @var{type} is the C type for variables set
+by options using this enumeration together with @code{Var}.
+
+@item UnknownError(@var{message})
+The message @var{message} will be used as an error message if the
+argument is invalid; for enumerations without @code{UnknownError}, a
+generic error message is used. @var{message} should contain a single
+@samp{%qs} format, which will be used to format the invalid argument.
+@end table
+
+@item
+An enumeration value record to define one of the strings in a set
+given in an @samp{Enum} record. These records have two fields: the
+string @samp{EnumValue} and a space-separated list of properties.
+Properties use the same format as option properties; the following are
+valid:
+@table @code
+@item Enum(@var{name})
+This property is required; @var{name} says which @samp{Enum} record
+this @samp{EnumValue} record corresponds to.
+
+@item String(@var{string})
+This property is required; @var{string} is the string option argument
+being described by this record.
+
+@item Value(@var{value})
+This property is required; it says what value (representable as
+@code{int}) should be used for the given string.
+
+@item Canonical
+This property is optional. If present, it says the present string is
+the canonical one among all those with the given value. Other strings
+yielding that value will be mapped to this one so specs do not need to
+handle them.
+
+@item DriverOnly
+This property is optional. If present, the present string will only
+be accepted by the driver. This is used for cases such as
+@option{-march=native} that are processed by the driver so that
+@samp{gcc -v} shows how the options chosen depended on the system on
+which the compiler was run.
+@end table
+
+@item
An option definition record. These records have the following fields:
@enumerate
@item
propagate through the @code{Negative} property of the option to be
turned off.
+As a consequence, if you have a group of mutually-exclusive
+options, their @code{Negative} properties should form a circular chain.
+For example, if options @option{-@var{a}}, @option{-@var{b}} and
+@option{-@var{c}} are mutually exclusive, their respective @code{Negative}
+properties should be @samp{Negative(@var{b})}, @samp{Negative(@var{c})}
+and @samp{Negative(@var{a})}.
+
@item Joined
@itemx Separate
The option takes a mandatory argument. @code{Joined} indicates
@samp{%qs} format, which will be used to format the name of the option
passed.
+@item Args(@var{n})
+For an option marked @code{Separate}, indicate that it takes @var{n}
+arguments. The default is 1.
+
@item UInteger
The option's argument is a non-negative integer. The option parser
will check and convert the argument before passing it to the relevant
@code{-falign-loops}=@var{n} are supported to make sure the saved
options are given a full integer.
+@item ToLower
+The option's argument should be converted to lowercase as part of
+putting it in canonical form, and before comparing with the strings
+indicated by any @code{Enum} property.
+
@item NoDriverArg
For an option marked @code{Separate}, the option only takes an
argument in the compiler proper, not in the driver. This is for
@var{var} is an integer variable that stores the value of the argument.
@item
+If the option takes an argument and has the @code{Enum} property,
+@var{var} is a variable (type given in the @code{Type} property of the
+@samp{Enum} record whose @code{Name} property has the same argument as
+the @code{Enum} property of this option) that stores the value of the
+argument.
+
+@item
+If the option has the @code{Defer} property, @var{var} is a pointer to
+a @code{VEC(cl_deferred_option,heap)} that stores the option for later
+processing. (@var{var} is declared with type @code{void *} and needs
+to be cast to @code{VEC(cl_deferred_option,heap)} before use.)
+
+@item
Otherwise, if the option takes an argument, @var{var} is a pointer to
the argument string. The pointer will be null if the argument is optional
and wasn't given.
The first option should use @samp{Mask(@var{name})} and the others
should use @samp{Mask(@var{name}) MaskExists}.
+@item Enum(@var{name})
+The option's argument is a string from the set of strings associated
+with the corresponding @samp{Enum} record. The string is checked and
+converted to the integer specified in the corresponding
+@samp{EnumValue} record before being passed to option handlers.
+
+@item Defer
+The option should be stored in a vector, specified with @code{Var},
+for later processing.
+
@item Alias(@var{opt})
@itemx Alias(@var{opt}, @var{arg})
@itemx Alias(@var{opt}, @var{posarg}, @var{negarg})
-The option is an alias for @option{-@var{opt}}. In the first form,
+The option is an alias for @option{-@var{opt}} (or the negative form
+of that option, depending on @code{NegativeAlias}). In the first form,
any argument passed to the alias is considered to be passed to
@option{-@var{opt}}, and @option{-@var{opt}} is considered to be
negated if the alias is used in negated form. In the second form, the
for it; only the canonical form of the option will be seen in those
places.
+@item NegativeAlias
+For an option marked with @code{Alias(@var{opt})}, the option is
+considered to be an alias for the positive form of @option{-@var{opt}}
+if negated and for the negative form of @option{-@var{opt}} if not
+negated. @code{NegativeAlias} may not be used with the forms of
+@code{Alias} taking more than one argument.
+
@item Ignore
This option is ignored apart from printing any warning specified using
@code{Warn}. The option will not be seen by specs and no @samp{OPT_}
@item Report
The state of the option should be printed by @option{-fverbose-asm}.
+@item Warning
+This is a warning option and should be shown as such in
+@option{--help} output. This flag does not currently affect anything
+other than @option{--help}.
+
+@item Optimization
+This is an optimization option. It should be shown as such in
+@option{--help} output, and any associated variable named using
+@code{Var} should be saved and restored when the optimization level is
+changed with @code{optimize} attributes.
+
@item Undocumented
The option is deliberately missing documentation and should not
be included in the @option{--help} output.
Build the @code{cl_target_option} structure to hold a copy of the
option, add the functions @code{cl_target_option_save} and
@code{cl_target_option_restore} to save and restore the options.
+
+@item SetByCombined
+The option may also be set by a combined option such as
+@option{-ffast-math}. This causes the @code{gcc_options} struct to
+have a field @code{frontend_set_@var{name}}, where @code{@var{name}}
+is the name of the field holding the value of this option (without the
+leading @code{x_}). This gives the front end a way to indicate that
+the value has been set explicitly and should not be changed by the
+combined option. For example, some front ends use this to prevent
+@option{-ffast-math} and @option{-fno-fast-math} from changing the
+value of @option{-fmath-errno} for languages that do not use
+@code{errno}.
+
@end table
OSDN Git Service
