\b \i\c{all} is an group alias for \e{all} warning classes.  Thus, \c{-w+all}
enables all available warnings, and \c{-w-all} disables warnings
entirely (since NASM 2.13).

\b \i\c{bad-pragma} is a backwards compatibility alias for \c{pragma-bad}.

\b \i\c{bnd} warns about ineffective use of the \c{BND} prefix when the
\c{JMP} instruction is converted to the \c{SHORT} form.
This should be extremely rare since the short \c{JMP} only
is applicable to jumps inside the same module, but if
it is legitimate, it may be necessary to use
\c{bnd jmp dword}.

\> Enabled by default.

\b \i\c{db-empty} warns about a \c{DB}, \c{DW}, etc declaration
with no operands, producing no output.
This is permitted, but often indicative of an error.
See \k{db}.

\> Enabled by default.

\b \i\c{environment} warns if a nonexistent environment variable
is accessed using the \c{%!} preprocessor
construct (see \k{getenv}.)  Such environment
variables are treated as empty (with this
warning issued) starting in NASM 2.15;
earlier versions of NASM would treat this as
an error.

\> Enabled by default.

\b \i\c{float} is a group alias for all warning classes prefixed by \c{float-}; currently
\c{float-denorm}, \c{float-overflow}, \c{float-toolong}, and \c{float-underflow}.

\b \i\c{float-denorm} warns about denormal floating point constants.

\> Disabled by default.

\b \i\c{float-overflow} warns about floating point underflow.

\> Enabled by default.

\b \i\c{float-toolong} warns about too many digits in floating-point numbers.

\> Enabled by default.

\b \i\c{float-underflow} warns about floating point underflow (a nonzero
constant rounded to zero.)

\> Disabled by default.

\b \i\c{hle} warns about invalid use of the HLE \c{XACQUIRE} or \c{XRELEASE}
prefixes.

\> Enabled by default.

\b \i\c{label} is a group alias for all warning classes prefixed by \c{label-}; currently
\c{label-orphan}, \c{label-redef}, and \c{label-redef-late}.

\b \i\c{label-orphan} warns about source lines which contain no instruction but define
a label without a trailing colon. This is most likely indicative
of a typo, but is technically correct NASM syntax (see \k{syntax}.)

\> Enabled by default.

\b \i\c{label-redef} warns if a label is defined more than once, but the
value is identical. It is an unconditional error to
define the same label more than once to \e{different} values.

\> Disabled by default.

\b \i\c{label-redef-late} the value of a label changed during the final, code-generation
pass. This may be the result of strange use of the
preprocessor. This is very likely to produce incorrect code and
may end up being an unconditional error in a future
version of NASM.

\> Enabled and promoted to error by default.

\b \i\c{lock} warns about \c{LOCK} prefixes on unlockable instructions.

\> Enabled by default.

\b \i\c{macro} is a group alias for all warning classes prefixed by \c{macro-}; currently
\c{macro-defaults}, \c{macro-params-legacy}, \c{macro-params-multi}, and \c{macro-params-single}.

\b \i\c{macro-defaults} warns when a macro has more default parameters than optional parameters.
See \k{mlmacdef} for why might want to disable this warning.

\> Enabled by default.

\b \i\c{macro-params} is a group alias for all warning classes prefixed by \c{macro-params-}; currently
\c{macro-params-legacy}, \c{macro-params-multi}, and \c{macro-params-single}.

\b \i\c{macro-params-legacy} warns about \i{multi-line macros} being invoked
with the wrong number of parameters, but for bug-compatibility
with NASM versions older than 2.15, NASM tried to fix up the
parameters to match the legacy behavior and call the macro anyway.
This can happen in certain cases where there are empty arguments
without braces, sometimes as a result of macro expansion.

\> The legacy behavior is quite strange and highly context-dependent,
and can be disabled with:

\c      %pragma preproc sane_empty_expansion true

\> It is highly recommended to use this option in new code.

\> Enabled by default.

\b \i\c{macro-params-multi} warns about \i{multi-line macros} being invoked
with the wrong number of parameters. See \k{mlmacover} for an
example of why you might want to disable this warning.

\> Enabled by default.

\b \i\c{macro-params-single} warns about \i{single-line macros} being invoked
with the wrong number of parameters.

\> Enabled by default.

\b \i\c{negative-rep} warns about negative counts given to the \c{%rep}
preprocessor directive.

\> Enabled by default.

\b \i\c{not-my-pragma} is a backwards compatibility alias for \c{pragma-na}.

\b \i\c{number-overflow} covers warnings about numeric constants which
don't fit in 64 bits.

\> Enabled by default.

\b \i\c{obsolete} is a group alias for all warning classes prefixed by \c{obsolete-}; currently
\c{obsolete-nop}, \c{obsolete-removed}, and \c{obsolete-valid}.

\b \i\c{obsolete-nop} warns for an instruction which has been removed
from the architecture, but has been architecturally
defined to be a noop for future CPUs.

\> Enabled by default.

\b \i\c{obsolete-removed} warns for an instruction which has been removed
from the architecture, and is no longer included
in the CPU definition given in the \c{[CPU]}
directive, for example \c{POP CS}, the opcode for
which, \c{0Fh}, instead is an opcode prefix on
CPUs newer than the first generation 8086.

\> Enabled by default.

\b \i\c{obsolete-valid} warns for an instruction which has been removed
from the architecture, but is still valid on the
specific CPU given in the \c{CPU} directive. Code
using these instructions is most likely not
forward compatible.

\> Enabled by default.

\b \i\c{orphan-labels} is a backwards compatibility alias for \c{label-orphan}.

\b \i\c{other} specifies any warning not included in any specific warning class.

\> Enabled by default.

\b \i\c{phase} warns about symbols having changed values during
the second-to-last assembly pass. This is not
inherently fatal, but may be a source of bugs.

\> Disabled by default.

\b \i\c{pragma} is a group alias for all warning classes prefixed by \c{pragma-}; currently
\c{pragma-bad}, \c{pragma-empty}, \c{pragma-na}, and \c{pragma-unknown}.

\b \i\c{pragma-bad} warns about a malformed or otherwise unparsable
\c{%pragma} directive.

\> Disabled by default.

\b \i\c{pragma-empty} warns about a \c{%pragma} directive containing nothing.
This is treated identically to \c{%pragma ignore} except
for this optional warning.

\> Disabled by default.

\b \i\c{pragma-na} warns about a \c{%pragma} directive which is not applicable to
this particular assembly session.  This is not yet implemented.

\> Disabled by default.

\b \i\c{pragma-unknown} warns about an unknown \c{%pragma} directive.
This is not yet implemented for most cases.

\> Disabled by default.

\b \i\c{ptr} warns about keywords used in other assemblers that might
indicate a mistake in the source code.  Currently only the MASM
\c{PTR} keyword is recognized. See also \k{pkg_masm}.

\> Enabled by default.

\b \i\c{regsize} warns about a register with implicit size (such as \c{EAX}, which is always 32 bits)
been given an explicit size specification which is inconsistent with the size
of the named register, e.g. \c{WORD EAX}. \c{DWORD EAX} or \c{WORD AX} are
permitted, and do not trigger this warning. Some registers which \e{do not} imply
a specific size, such as \c{K0}, may need this specification unless the instruction
itself implies the instruction size:

\c      KMOVW K0,[foo]          ; Permitted, KMOVW implies 16 bits
\c      KMOV  WORD K0,[foo]     ; Permitted, WORD K0 specifies instruction size
\c      KMOV  K0,WORD [foo]     ; Permitted, WORD [foo] specifies instruction size
\c      KMOV  K0,[foo]          ; Not permitted, instruction size ambiguous

\> Enabled by default.

\b \i\c{unknown-pragma} is a backwards compatibility alias for \c{pragma-unknown}.

\b \i\c{unknown-warning} warns about a \c{-w} or \c{-W} option or a \c{[WARNING]} directive
that contains an unknown warning name or is otherwise not possible to process.

\> Disabled by default.

\b \i\c{user} controls output of \c{%warning} directives (see \k{pperror}).

\> Enabled by default.

\b \i\c{warn-stack-empty} a [WARNING POP] directive was executed when
the warning stack is empty. This is treated
as a [WARNING *all] directive.

\> Enabled by default.

\b \i\c{zeroing} a \c{RESx} directive was used in a section which contains
initialized data, and the output format does not support
this. Instead, this will be replaced with explicit zero
content, which may produce a large output file.

\> Enabled by default.

\b \i\c{zext-reloc} warns that a relocation has been zero-extended due
to limitations in the output format.

\> Enabled by default.

