AS(1)                        GNU Development Tools                       AS(1)



NAME
       AS - the portable GNU assembler.

SYNOPSIS
       as [-a[cdghlns][=file]] [--alternate] [-D]
        [--compress-debug-sections]  [--nocompress-debug-sections]
        [--debug-prefix-map old=new]
        [--defsym sym=val] [-f] [-g] [--gstabs]
        [--gstabs+] [--gdwarf-2] [--gdwarf-sections]
        [--help] [-I dir] [-J]
        [-K] [-L] [--listing-lhs-width=NUM]
        [--listing-lhs-width2=NUM] [--listing-rhs-width=NUM]
        [--listing-cont-lines=NUM] [--keep-locals] [-o
        objfile] [-R] [--reduce-memory-overheads] [--statistics]
        [-v] [-version] [--version] [-W] [--warn]
        [--fatal-warnings] [-w] [-x] [-Z] [@FILE]
        [--size-check=[error|warning]]
        [--target-help] [target-options]
        [--|files ...]

       Target AArch64 options:
          [-EB|-EL]
          [-mabi=ABI]

       Target Alpha options:
          [-mcpu]
          [-mdebug | -no-mdebug]
          [-replace | -noreplace]
          [-relax] [-g] [-Gsize]
          [-F] [-32addr]

       Target ARC options:
          [-marc[5|6|7|8]]
          [-EB|-EL]

       Target ARM options:
          [-mcpu=processor[+extension...]]
          [-march=architecture[+extension...]]
          [-mfpu=floating-point-format]
          [-mfloat-abi=abi]
          [-meabi=ver]
          [-mthumb]
          [-EB|-EL]
          [-mapcs-32|-mapcs-26|-mapcs-float|
           -mapcs-reentrant]
          [-mthumb-interwork] [-k]

       Target Blackfin options:
          [-mcpu=processor[-sirevision]]
          [-mfdpic]
          [-mno-fdpic]
          [-mnopic]

       Target CRIS options:
          [--underscore | --no-underscore]
          [--pic] [-N]
          [--emulation=criself | --emulation=crisaout]
          [--march=v0_v10 | --march=v10 | --march=v32 |
       --march=common_v10_v32]

       Target D10V options:
          [-O]

       Target D30V options:
          [-O|-n|-N]

       Target EPIPHANY options:
          [-mepiphany|-mepiphany16]

       Target H8/300 options:
          [-h-tick-hex]

       Target i386 options:
          [--32|--x32|--64] [-n]
          [-march=CPU[+EXTENSION...]] [-mtune=CPU]

       Target i960 options:
          [-ACA|-ACA_A|-ACB|-ACC|-AKA|-AKB|
           -AKC|-AMC]
          [-b] [-no-relax]

       Target IA-64 options:
          [-mconstant-gp|-mauto-pic]
          [-milp32|-milp64|-mlp64|-mp64]
          [-mle|mbe]
          [-mtune=itanium1|-mtune=itanium2]
          [-munwind-check=warning|-munwind-check=error]
          [-mhint.b=ok|-mhint.b=warning|-mhint.b=error]
          [-x|-xexplicit] [-xauto] [-xdebug]

       Target IP2K options:
          [-mip2022|-mip2022ext]

       Target M32C options:
          [-m32c|-m16c] [-relax] [-h-tick-hex]

       Target M32R options:
          [--m32rx|--[no-]warn-explicit-parallel-conflicts|
          --W[n]p]

       Target M680X0 options:
          [-l] [-m68000|-m68010|-m68020|...]

       Target M68HC11 options:
          [-m68hc11|-m68hc12|-m68hcs12|-mm9s12x|-mm9s12xg]
          [-mshort|-mlong]
          [-mshort-double|-mlong-double]
          [--force-long-branches] [--short-branches]
          [--strict-direct-mode] [--print-insn-syntax]
          [--print-opcodes] [--generate-example]

       Target MCORE options:
          [-jsri2bsr] [-sifilter] [-relax]
          [-mcpu=[210|340]]

       Target Meta options:
          [-mcpu=cpu] [-mfpu=cpu] [-mdsp=cpu] Target MICROBLAZE options:

       Target MIPS options:
          [-nocpp] [-EL] [-EB] [-O[optimization level]]
          [-g[debug level]] [-G num] [-KPIC] [-call_shared]
          [-non_shared] [-xgot [-mvxworks-pic]
          [-mabi=ABI] [-32] [-n32] [-64] [-mfp32] [-mgp32]
          [-mfp64] [-mgp64] [-mfpxx]
          [-modd-spreg] [-mno-odd-spreg]
          [-march=CPU] [-mtune=CPU] [-mips1] [-mips2]
          [-mips3] [-mips4] [-mips5] [-mips32] [-mips32r2]
          [-mips32r3] [-mips32r5] [-mips32r6] [-mips64] [-mips64r2]
          [-mips64r3] [-mips64r5] [-mips64r6]
          [-construct-floats] [-no-construct-floats]
          [-mnan=encoding]
          [-trap] [-no-break] [-break] [-no-trap]
          [-mips16] [-no-mips16]
          [-mmicromips] [-mno-micromips]
          [-msmartmips] [-mno-smartmips]
          [-mips3d] [-no-mips3d]
          [-mdmx] [-no-mdmx]
          [-mdsp] [-mno-dsp]
          [-mdspr2] [-mno-dspr2]
          [-mmsa] [-mno-msa]
          [-mxpa] [-mno-xpa]
          [-mmt] [-mno-mt]
          [-mmcu] [-mno-mcu]
          [-minsn32] [-mno-insn32]
          [-mfix7000] [-mno-fix7000]
          [-mfix-rm7000] [-mno-fix-rm7000]
          [-mfix-vr4120] [-mno-fix-vr4120]
          [-mfix-vr4130] [-mno-fix-vr4130]
          [-mdebug] [-no-mdebug]
          [-mpdr] [-mno-pdr]

       Target MMIX options:
          [--fixed-special-register-names] [--globalize-symbols]
          [--gnu-syntax] [--relax] [--no-predefined-symbols]
          [--no-expand] [--no-merge-gregs] [-x]
          [--linker-allocated-gregs]

       Target Nios II options:
          [-relax-all] [-relax-section] [-no-relax]
          [-EB] [-EL]

       Target NDS32 options:
           [-EL] [-EB] [-O] [-Os] [-mcpu=cpu]
           [-misa=isa] [-mabi=abi] [-mall-ext]
           [-m[no-]16-bit]  [-m[no-]perf-ext] [-m[no-]perf2-ext]
           [-m[no-]string-ext] [-m[no-]dsp-ext] [-m[no-]mac] [-m[no-]div]
           [-m[no-]audio-isa-ext] [-m[no-]fpu-sp-ext] [-m[no-]fpu-dp-ext]
           [-m[no-]fpu-fma] [-mfpu-freg=FREG] [-mreduced-regs]
           [-mfull-regs] [-m[no-]dx-regs] [-mpic] [-mno-relax]
           [-mb2bb]

       Target PDP11 options:
          [-mpic|-mno-pic] [-mall] [-mno-extensions]
          [-mextension|-mno-extension]
          [-mcpu] [-mmachine]

       Target picoJava options:
          [-mb|-me]

       Target PowerPC options:
          [-a32|-a64]
          [-mpwrx|-mpwr2|-mpwr|-m601|-mppc|-mppc32|-m603|-m604|-m403|-m405|
           -m440|-m464|-m476|-m7400|-m7410|-m7450|-m7455|-m750cl|-mppc64|
           -m620|-me500|-e500x2|-me500mc|-me500mc64|-me5500|-me6500|-mppc64bridge|
           -mbooke|-mpower4|-mpwr4|-mpower5|-mpwr5|-mpwr5x|-mpower6|-mpwr6|
           -mpower7|-mpwr7|-mpower8|-mpwr8|-ma2|-mcell|-mspe|-mtitan|-me300|-mcom]
          [-many] [-maltivec|-mvsx|-mhtm|-mvle]
          [-mregnames|-mno-regnames]
          [-mrelocatable|-mrelocatable-lib|-K PIC] [-memb]
          [-mlittle|-mlittle-endian|-le|-mbig|-mbig-endian|-be]
          [-msolaris|-mno-solaris]
          [-nops=count]

       Target RL78 options:
          [-mg10]
          [-m32bit-doubles|-m64bit-doubles]

       Target RX options:
          [-mlittle-endian|-mbig-endian]
          [-m32bit-doubles|-m64bit-doubles]
          [-muse-conventional-section-names]
          [-msmall-data-limit]
          [-mpid]
          [-mrelax]
          [-mint-register=number]
          [-mgcc-abi|-mrx-abi]

       Target s390 options:
          [-m31|-m64] [-mesa|-mzarch] [-march=CPU]
          [-mregnames|-mno-regnames]
          [-mwarn-areg-zero]

       Target SCORE options:
          [-EB][-EL][-FIXDD][-NWARN]
          [-SCORE5][-SCORE5U][-SCORE7][-SCORE3]
          [-march=score7][-march=score3]
          [-USE_R1][-KPIC][-O0][-G num][-V]

       Target SPARC options:
          [-Av6|-Av7|-Av8|-Asparclet|-Asparclite
           -Av8plus|-Av8plusa|-Av9|-Av9a]
          [-xarch=v8plus|-xarch=v8plusa] [-bump]
          [-32|-64]

       Target TIC54X options:
        [-mcpu=54[123589]|-mcpu=54[56]lp] [-mfar-mode|-mf]
        [-merrors-to-file <filename>|-me <filename>]

       Target TIC6X options:
          [-march=arch] [-mbig-endian|-mlittle-endian]
          [-mdsbt|-mno-dsbt] [-mpid=no|-mpid=near|-mpid=far]
          [-mpic|-mno-pic]

       Target TILE-Gx options:
          [-m32|-m64][-EB][-EL]

       Target Xtensa options:
        [--[no-]text-section-literals] [--[no-]absolute-literals]
        [--[no-]target-align] [--[no-]longcalls]
        [--[no-]transform]
        [--rename-section oldname=newname]
        [--[no-]trampolines]

       Target Z80 options:
         [-z80] [-r800]
         [ -ignore-undocumented-instructions] [-Wnud]
         [ -ignore-unportable-instructions] [-Wnup]
         [ -warn-undocumented-instructions] [-Wud]
         [ -warn-unportable-instructions] [-Wup]
         [ -forbid-undocumented-instructions] [-Fud]
         [ -forbid-unportable-instructions] [-Fup]

DESCRIPTION
       GNU as is really a family of assemblers.  If you use (or have used) the
       GNU assembler on one architecture, you should find a fairly similar
       environment when you use it on another architecture.  Each version has
       much in common with the others, including object file formats, most
       assembler directives (often called pseudo-ops) and assembler syntax.

       as is primarily intended to assemble the output of the GNU C compiler
       "gcc" for use by the linker "ld".  Nevertheless, we've tried to make as
       assemble correctly everything that other assemblers for the same
       machine would assemble.  Any exceptions are documented explicitly.
       This doesn't mean as always uses the same syntax as another assembler
       for the same architecture; for example, we know of several incompatible
       versions of 680x0 assembly language syntax.

       Each time you run as it assembles exactly one source program.  The
       source program is made up of one or more files.  (The standard input is
       also a file.)

       You give as a command line that has zero or more input file names.  The
       input files are read (from left file name to right).  A command line
       argument (in any position) that has no special meaning is taken to be
       an input file name.

       If you give as no file names it attempts to read one input file from
       the as standard input, which is normally your terminal.  You may have
       to type ctl-D to tell as there is no more program to assemble.

       Use -- if you need to explicitly name the standard input file in your
       command line.

       If the source is empty, as produces a small, empty object file.

       as may write warnings and error messages to the standard error file
       (usually your terminal).  This should not happen when  a compiler runs
       as automatically.  Warnings report an assumption made so that as could
       keep assembling a flawed program; errors report a grave problem that
       stops the assembly.

       If you are invoking as via the GNU C compiler, you can use the -Wa
       option to pass arguments through to the assembler.  The assembler
       arguments must be separated from each other (and the -Wa) by commas.
       For example:

               gcc -c -g -O -Wa,-alh,-L file.c

       This passes two options to the assembler: -alh (emit a listing to
       standard output with high-level and assembly source) and -L (retain
       local symbols in the symbol table).

       Usually you do not need to use this -Wa mechanism, since many compiler
       command-line options are automatically passed to the assembler by the
       compiler.  (You can call the GNU compiler driver with the -v option to
       see precisely what options it passes to each compilation pass,
       including the assembler.)

OPTIONS
       @file
           Read command-line options from file.  The options read are inserted
           in place of the original @file option.  If file does not exist, or
           cannot be read, then the option will be treated literally, and not
           removed.

           Options in file are separated by whitespace.  A whitespace
           character may be included in an option by surrounding the entire
           option in either single or double quotes.  Any character (including
           a backslash) may be included by prefixing the character to be
           included with a backslash.  The file may itself contain additional
           @file options; any such options will be processed recursively.

       -a[cdghlmns]
           Turn on listings, in any of a variety of ways:

           -ac omit false conditionals

           -ad omit debugging directives

           -ag include general information, like as version and options passed

           -ah include high-level source

           -al include assembly

           -am include macro expansions

           -an omit forms processing

           -as include symbols

           =file
               set the name of the listing file

           You may combine these options; for example, use -aln for assembly
           listing without forms processing.  The =file option, if used, must
           be the last one.  By itself, -a defaults to -ahls.

       --alternate
           Begin in alternate macro mode.

       --compress-debug-sections
           Compress DWARF debug sections using zlib.  The debug sections are
           renamed to begin with .zdebug, and the resulting object file may
           not be compatible with older linkers and object file utilities.

       --nocompress-debug-sections
           Do not compress DWARF debug sections.  This is the default.

       -D  Ignored.  This option is accepted for script compatibility with
           calls to other assemblers.

       --debug-prefix-map old=new
           When assembling files in directory old, record debugging
           information describing them as in new instead.

       --defsym sym=value
           Define the symbol sym to be value before assembling the input file.
           value must be an integer constant.  As in C, a leading 0x indicates
           a hexadecimal value, and a leading 0 indicates an octal value.  The
           value of the symbol can be overridden inside a source file via the
           use of a ".set" pseudo-op.

       -f  "fast"---skip whitespace and comment preprocessing (assume source
           is compiler output).

       -g
       --gen-debug
           Generate debugging information for each assembler source line using
           whichever debug format is preferred by the target.  This currently
           means either STABS, ECOFF or DWARF2.

       --gstabs
           Generate stabs debugging information for each assembler line.  This
           may help debugging assembler code, if the debugger can handle it.

       --gstabs+
           Generate stabs debugging information for each assembler line, with
           GNU extensions that probably only gdb can handle, and that could
           make other debuggers crash or refuse to read your program.  This
           may help debugging assembler code.  Currently the only GNU
           extension is the location of the current working directory at
           assembling time.

       --gdwarf-2
           Generate DWARF2 debugging information for each assembler line.
           This may help debugging assembler code, if the debugger can handle
           it.  Note---this option is only supported by some targets, not all
           of them.

       --gdwarf-sections
           Instead of creating a .debug_line section, create a series of
           .debug_line.foo sections where foo is the name of the corresponding
           code section.  For example a code section called .text.func will
           have its dwarf line number information placed into a section called
           .debug_line.text.func.  If the code section is just called .text
           then debug line section will still be called just .debug_line
           without any suffix.

       --size-check=error
       --size-check=warning
           Issue an error or warning for invalid ELF .size directive.

       --help
           Print a summary of the command line options and exit.

       --target-help
           Print a summary of all target specific options and exit.

       -I dir
           Add directory dir to the search list for ".include" directives.

       -J  Don't warn about signed overflow.

       -K  Issue warnings when difference tables altered for long
           displacements.

       -L
       --keep-locals
           Keep (in the symbol table) local symbols.  These symbols start with
           system-specific local label prefixes, typically .L for ELF systems
           or L for traditional a.out systems.

       --listing-lhs-width=number
           Set the maximum width, in words, of the output data column for an
           assembler listing to number.

       --listing-lhs-width2=number
           Set the maximum width, in words, of the output data column for
           continuation lines in an assembler listing to number.

       --listing-rhs-width=number
           Set the maximum width of an input source line, as displayed in a
           listing, to number bytes.

       --listing-cont-lines=number
           Set the maximum number of lines printed in a listing for a single
           line of input to number + 1.

       -o objfile
           Name the object-file output from as objfile.

       -R  Fold the data section into the text section.

           Set the default size of GAS's hash tables to a prime number close
           to number.  Increasing this value can reduce the length of time it
           takes the assembler to perform its tasks, at the expense of
           increasing the assembler's memory requirements.  Similarly reducing
           this value can reduce the memory requirements at the expense of
           speed.

       --reduce-memory-overheads
           This option reduces GAS's memory requirements, at the expense of
           making the assembly processes slower.  Currently this switch is a
           synonym for --hash-size=4051, but in the future it may have other
           effects as well.

       --statistics
           Print the maximum space (in bytes) and total time (in seconds) used
           by assembly.

       --strip-local-absolute
           Remove local absolute symbols from the outgoing symbol table.

       -v
       -version
           Print the as version.

       --version
           Print the as version and exit.

       -W
       --no-warn
           Suppress warning messages.

       --fatal-warnings
           Treat warnings as errors.

       --warn
           Don't suppress warning messages or treat them as errors.

       -w  Ignored.

       -x  Ignored.

       -Z  Generate an object file even after errors.

       -- | files ...
           Standard input, or source files to assemble.

       The following options are available when as is configured for the
       64-bit mode of the ARM Architecture (AArch64).

       -EB This option specifies that the output generated by the assembler
           should be marked as being encoded for a big-endian processor.

       -EL This option specifies that the output generated by the assembler
           should be marked as being encoded for a little-endian processor.

       -mabi=abi
           Specify which ABI the source code uses.  The recognized arguments
           are: "ilp32" and "lp64", which decides the generated object file in
           ELF32 and ELF64 format respectively.  The default is "lp64".

       -mcpu=processor[+extension...]
           This option specifies the target processor.  The assembler will
           issue an error message if an attempt is made to assemble an
           instruction which will not execute on the target processor.  The
           following processor names are recognized: "cortex-a53",
           "cortex-a57", "thunderx", "xgene1", and "xgene2".  The special name
           "all" may be used to allow the assembler to accept instructions
           valid for any supported processor, including all optional
           extensions.

           In addition to the basic instruction set, the assembler can be told
           to accept, or restrict, various extension mnemonics that extend the
           processor.

           If some implementations of a particular processor can have an
           extension, then then those extensions are automatically enabled.
           Consequently, you will not normally have to specify any additional
           extensions.

       -march=architecture[+extension...]
           This option specifies the target architecture.  The assembler will
           issue an error message if an attempt is made to assemble an
           instruction which will not execute on the target architecture.  The
           only value for architecture is "armv8-a".

           If both -mcpu and -march are specified, the assembler will use the
           setting for -mcpu.  If neither are specified, the assembler will
           default to -mcpu=all.

           The architecture option can be extended with the same instruction
           set extension options as the -mcpu option.  Unlike -mcpu,
           extensions are not always enabled by default,

       -mverbose-error
           This option enables verbose error messages for AArch64 gas.  This
           option is enabled by default.

       -mno-verbose-error
           This option disables verbose error messages in AArch64 gas.

       The following options are available when as is configured for an Alpha
       processor.

       -mcpu
           This option specifies the target processor.  If an attempt is made
           to assemble an instruction which will not execute on the target
           processor, the assembler may either expand the instruction as a
           macro or issue an error message.  This option is equivalent to the
           ".arch" directive.

           The following processor names are recognized: 21064, "21064a",
           21066, 21068, 21164, "21164a", "21164pc", 21264, "21264a",
           "21264b", "ev4", "ev5", "lca45", "ev5", "ev56", "pca56", "ev6",
           "ev67", "ev68".  The special name "all" may be used to allow the
           assembler to accept instructions valid for any Alpha processor.

           In order to support existing practice in OSF/1 with respect to
           ".arch", and existing practice within MILO (the Linux ARC
           bootloader), the numbered processor names (e.g. 21064) enable the
           processor-specific PALcode instructions, while the "electro-vlasic"
           names (e.g. "ev4") do not.

       -mdebug
       -no-mdebug
           Enables or disables the generation of ".mdebug" encapsulation for
           stabs directives and procedure descriptors.  The default is to
           automatically enable ".mdebug" when the first stabs directive is
           seen.

       -relax
           This option forces all relocations to be put into the object file,
           instead of saving space and resolving some relocations at assembly
           time.  Note that this option does not propagate all symbol
           arithmetic into the object file, because not all symbol arithmetic
           can be represented.  However, the option can still be useful in
           specific applications.

       -replace
       -noreplace
           Enables or disables the optimization of procedure calls, both at
           assemblage and at link time.  These options are only available for
           VMS targets and "-replace" is the default.  See section 1.4.1 of
           the OpenVMS Linker Utility Manual.

       -g  This option is used when the compiler generates debug information.
           When gcc is using mips-tfile to generate debug information for
           ECOFF, local labels must be passed through to the object file.
           Otherwise this option has no effect.

       -Gsize
           A local common symbol larger than size is placed in ".bss", while
           smaller symbols are placed in ".sbss".

       -F
       -32addr
           These options are ignored for backward compatibility.

       The following options are available when as is configured for an ARC
       processor.

       -marc[5|6|7|8]
           This option selects the core processor variant.

       -EB | -EL
           Select either big-endian (-EB) or little-endian (-EL) output.

       The following options are available when as is configured for the ARM
       processor family.

       -mcpu=processor[+extension...]
           Specify which ARM processor variant is the target.

       -march=architecture[+extension...]
           Specify which ARM architecture variant is used by the target.

       -mfpu=floating-point-format
           Select which Floating Point architecture is the target.

       -mfloat-abi=abi
           Select which floating point ABI is in use.

       -mthumb
           Enable Thumb only instruction decoding.

       -mapcs-32 | -mapcs-26 | -mapcs-float | -mapcs-reentrant
           Select which procedure calling convention is in use.

       -EB | -EL
           Select either big-endian (-EB) or little-endian (-EL) output.

       -mthumb-interwork
           Specify that the code has been generated with interworking between
           Thumb and ARM code in mind.

       -mccs
           Turns on CodeComposer Studio assembly syntax compatibility mode.

       -k  Specify that PIC code has been generated.

       The following options are available when as is configured for the
       Blackfin processor family.

       -mcpu=processor[-sirevision]
           This option specifies the target processor.  The optional
           sirevision is not used in assembler.  It's here such that GCC can
           easily pass down its "-mcpu=" option.  The assembler will issue an
           error message if an attempt is made to assemble an instruction
           which will not execute on the target processor.  The following
           processor names are recognized: "bf504", "bf506", "bf512", "bf514",
           "bf516", "bf518", "bf522", "bf523", "bf524", "bf525", "bf526",
           "bf527", "bf531", "bf532", "bf533", "bf534", "bf535" (not
           implemented yet), "bf536", "bf537", "bf538", "bf539", "bf542",
           "bf542m", "bf544", "bf544m", "bf547", "bf547m", "bf548", "bf548m",
           "bf549", "bf549m", "bf561", and "bf592".

       -mfdpic
           Assemble for the FDPIC ABI.

       -mno-fdpic
       -mnopic
           Disable -mfdpic.

       See the info pages for documentation of the CRIS-specific options.

       The following options are available when as is configured for a D10V
       processor.

       -O  Optimize output by parallelizing instructions.

       The following options are available when as is configured for a D30V
       processor.

       -O  Optimize output by parallelizing instructions.

       -n  Warn when nops are generated.

       -N  Warn when a nop after a 32-bit multiply instruction is generated.

       The following options are available when as is configured for an
       Epiphany processor.

       -mepiphany
           Specifies that the both 32 and 16 bit instructions are allowed.
           This is the default behavior.

       -mepiphany16
           Restricts the permitted instructions to just the 16 bit set.

       The following options are available when as is configured for an H8/300
       processor.  @chapter H8/300 Dependent Features

   Options
       The Renesas H8/300 version of "as" has one machine-dependent option:

       -h-tick-hex
           Support H'00 style hex constants in addition to 0x00 style.

       The following options are available when as is configured for an i386
       processor.

       --32 | --x32 | --64
           Select the word size, either 32 bits or 64 bits.  --32 implies
           Intel i386 architecture, while --x32 and --64 imply AMD x86-64
           architecture with 32-bit or 64-bit word-size respectively.

           These options are only available with the ELF object file format,
           and require that the necessary BFD support has been included (on a
           32-bit platform you have to add --enable-64-bit-bfd to configure
           enable 64-bit usage and use x86-64 as target platform).

       -n  By default, x86 GAS replaces multiple nop instructions used for
           alignment within code sections with multi-byte nop instructions
           such as leal 0(%esi,1),%esi.  This switch disables the
           optimization.

       --divide
           On SVR4-derived platforms, the character / is treated as a comment
           character, which means that it cannot be used in expressions.  The
           --divide option turns / into a normal character.  This does not
           disable / at the beginning of a line starting a comment, or affect
           using # for starting a comment.

       -march=CPU[+EXTENSION...]
           This option specifies the target processor.  The assembler will
           issue an error message if an attempt is made to assemble an
           instruction which will not execute on the target processor.  The
           following processor names are recognized: "i8086", "i186", "i286",
           "i386", "i486", "i586", "i686", "pentium", "pentiumpro",
           "pentiumii", "pentiumiii", "pentium4", "prescott", "nocona",
           "core", "core2", "corei7", "l1om", "k1om", "k6", "k6_2", "athlon",
           "opteron", "k8", "amdfam10", "bdver1", "bdver2", "bdver3",
           "bdver4", "btver1", "btver2", "generic32" and "generic64".

           In addition to the basic instruction set, the assembler can be told
           to accept various extension mnemonics.  For example,
           "-march=i686+sse4+vmx" extends i686 with sse4 and vmx.  The
           following extensions are currently supported: 8087, 287, 387,
           "no87", "mmx", "nommx", "sse", "sse2", "sse3", "ssse3", "sse4.1",
           "sse4.2", "sse4", "nosse", "avx", "avx2", "adx", "rdseed",
           "prfchw", "smap", "mpx", "sha", "prefetchwt1", "clflushopt", "se1",
           "clwb", "pcommit", "avx512f", "avx512cd", "avx512er", "avx512pf",
           "avx512vl", "avx512bw", "avx512dq", "avx512ifma", "avx512vbmi",
           "noavx", "vmx", "vmfunc", "smx", "xsave", "xsaveopt", "xsavec",
           "xsaves", "aes", "pclmul", "fsgsbase", "rdrnd", "f16c", "bmi2",
           "fma", "movbe", "ept", "lzcnt", "hle", "rtm", "invpcid", "clflush",
           "lwp", "fma4", "xop", "cx16", "syscall", "rdtscp", "3dnow",
           "3dnowa", "sse4a", "sse5", "svme", "abm" and "padlock".  Note that
           rather than extending a basic instruction set, the extension
           mnemonics starting with "no" revoke the respective functionality.

           When the ".arch" directive is used with -march, the ".arch"
           directive will take precedent.

       -mtune=CPU
           This option specifies a processor to optimize for. When used in
           conjunction with the -march option, only instructions of the
           processor specified by the -march option will be generated.

           Valid CPU values are identical to the processor list of -march=CPU.

       -msse2avx
           This option specifies that the assembler should encode SSE
           instructions with VEX prefix.

       -msse-check=none
       -msse-check=warning
       -msse-check=error
           These options control if the assembler should check SSE
           instructions.  -msse-check=none will make the assembler not to
           check SSE instructions,  which is the default.  -msse-check=warning
           will make the assembler issue a warning for any SSE instruction.
           -msse-check=error will make the assembler issue an error for any
           SSE instruction.

       -mavxscalar=128
       -mavxscalar=256
           These options control how the assembler should encode scalar AVX
           instructions.  -mavxscalar=128 will encode scalar AVX instructions
           with 128bit vector length, which is the default.  -mavxscalar=256
           will encode scalar AVX instructions with 256bit vector length.

       -mevexlig=128
       -mevexlig=256
       -mevexlig=512
           These options control how the assembler should encode length-
           ignored (LIG) EVEX instructions.  -mevexlig=128 will encode LIG
           EVEX instructions with 128bit vector length, which is the default.
           -mevexlig=256 and -mevexlig=512 will encode LIG EVEX instructions
           with 256bit and 512bit vector length, respectively.

       -mevexwig=0
       -mevexwig=1
           These options control how the assembler should encode w-ignored
           (WIG) EVEX instructions.  -mevexwig=0 will encode WIG EVEX
           instructions with evex.w = 0, which is the default.  -mevexwig=1
           will encode WIG EVEX instructions with evex.w = 1.

       -mmnemonic=att
       -mmnemonic=intel
           This option specifies instruction mnemonic for matching
           instructions.  The ".att_mnemonic" and ".intel_mnemonic" directives
           will take precedent.

       -msyntax=att
       -msyntax=intel
           This option specifies instruction syntax when processing
           instructions.  The ".att_syntax" and ".intel_syntax" directives
           will take precedent.

       -mnaked-reg
           This opetion specifies that registers don't require a % prefix.
           The ".att_syntax" and ".intel_syntax" directives will take
           precedent.

       -madd-bnd-prefix
           This option forces the assembler to add BND prefix to all branches,
           even if such prefix was not explicitly specified in the source
           code.

       -mbig-obj
           On x86-64 PE/COFF target this option forces the use of big object
           file format, which allows more than 32768 sections.

       -momit-lock-prefix=no
       -momit-lock-prefix=yes
           These options control how the assembler should encode lock prefix.
           This option is intended as a workaround for processors, that fail
           on lock prefix. This option can only be safely used with single-
           core, single-thread computers -momit-lock-prefix=yes will omit all
           lock prefixes.  -momit-lock-prefix=no will encode lock prefix as
           usual, which is the default.

       -mevexrcig=rne
       -mevexrcig=rd
       -mevexrcig=ru
       -mevexrcig=rz
           These options control how the assembler should encode SAE-only EVEX
           instructions.  -mevexrcig=rne will encode RC bits of EVEX
           instruction with 00, which is the default.  -mevexrcig=rd,
           -mevexrcig=ru and -mevexrcig=rz will encode SAE-only EVEX
           instructions with 01, 10 and 11 RC bits, respectively.

       The following options are available when as is configured for the Intel
       80960 processor.

       -ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB | -AKC | -AMC
           Specify which variant of the 960 architecture is the target.

       -b  Add code to collect statistics about branches taken.

       -no-relax
           Do not alter compare-and-branch instructions for long
           displacements; error if necessary.

       The following options are available when as is configured for the
       Ubicom IP2K series.

       -mip2022ext
           Specifies that the extended IP2022 instructions are allowed.

       -mip2022
           Restores the default behaviour, which restricts the permitted
           instructions to just the basic IP2022 ones.

       The following options are available when as is configured for the
       Renesas M32C and M16C processors.

       -m32c
           Assemble M32C instructions.

       -m16c
           Assemble M16C instructions (the default).

       -relax
           Enable support for link-time relaxations.

       -h-tick-hex
           Support H'00 style hex constants in addition to 0x00 style.

       The following options are available when as is configured for the
       Renesas M32R (formerly Mitsubishi M32R) series.

       --m32rx
           Specify which processor in the M32R family is the target.  The
           default is normally the M32R, but this option changes it to the
           M32RX.

       --warn-explicit-parallel-conflicts or --Wp
           Produce warning messages when questionable parallel constructs are
           encountered.

       --no-warn-explicit-parallel-conflicts or --Wnp
           Do not produce warning messages when questionable parallel
           constructs are encountered.

       The following options are available when as is configured for the
       Motorola 68000 series.

       -l  Shorten references to undefined symbols, to one word instead of
           two.

       -m68000 | -m68008 | -m68010 | -m68020 | -m68030
       | -m68040 | -m68060 | -m68302 | -m68331 | -m68332
       | -m68333 | -m68340 | -mcpu32 | -m5200
           Specify what processor in the 68000 family is the target.  The
           default is normally the 68020, but this can be changed at
           configuration time.

       -m68881 | -m68882 | -mno-68881 | -mno-68882
           The target machine does (or does not) have a floating-point
           coprocessor.  The default is to assume a coprocessor for 68020,
           68030, and cpu32.  Although the basic 68000 is not compatible with
           the 68881, a combination of the two can be specified, since it's
           possible to do emulation of the coprocessor instructions with the
           main processor.

       -m68851 | -mno-68851
           The target machine does (or does not) have a memory-management unit
           coprocessor.  The default is to assume an MMU for 68020 and up.

       The following options are available when as is configured for an Altera
       Nios II processor.

       -relax-section
           Replace identified out-of-range branches with PC-relative "jmp"
           sequences when possible.  The generated code sequences are suitable
           for use in position-independent code, but there is a practical
           limit on the extended branch range because of the length of the
           sequences.  This option is the default.

       -relax-all
           Replace branch instructions not determinable to be in range and all
           call instructions with "jmp" and "callr" sequences (respectively).
           This option generates absolute relocations against the target
           symbols and is not appropriate for position-independent code.

       -no-relax
           Do not replace any branches or calls.

       -EB Generate big-endian output.

       -EL Generate little-endian output.  This is the default.

       The following options are available when as is configured for a Meta
       processor.

       "-mcpu=metac11"
           Generate code for Meta 1.1.

       "-mcpu=metac12"
           Generate code for Meta 1.2.

       "-mcpu=metac21"
           Generate code for Meta 2.1.

       "-mfpu=metac21"
           Allow code to use FPU hardware of Meta 2.1.

       See the info pages for documentation of the MMIX-specific options.

       The following options are available when as is configured for a NDS32
       processor.

       "-O1"
           Optimize for performance.

       "-Os"
           Optimize for space.

       "-EL"
           Produce little endian data output.

       "-EB"
           Produce little endian data output.

       "-mpic"
           Generate PIC.

       "-mno-fp-as-gp-relax"
           Suppress fp-as-gp relaxation for this file.

       "-mb2bb-relax"
           Back-to-back branch optimization.

       "-mno-all-relax"
           Suppress all relaxation for this file.

       "-march=<arch name>"
           Assemble for architecture <arch name> which could be v3, v3j, v3m,
           v3f, v3s, v2, v2j, v2f, v2s.

       "-mbaseline=<baseline>"
           Assemble for baseline <baseline> which could be v2, v3, v3m.

       "-mfpu-freg=FREG"
           Specify a FPU configuration.

           "0      8 SP /  4 DP registers"
           "1     16 SP /  8 DP registers"
           "2     32 SP / 16 DP registers"
           "3     32 SP / 32 DP registers"
       "-mabi=abi"
           Specify a abi version <abi> could be v1, v2, v2fp, v2fpp.

       "-m[no-]mac"
           Enable/Disable Multiply instructions support.

       "-m[no-]div"
           Enable/Disable Divide instructions support.

       "-m[no-]16bit-ext"
           Enable/Disable 16-bit extension

       "-m[no-]dx-regs"
           Enable/Disable d0/d1 registers

       "-m[no-]perf-ext"
           Enable/Disable Performance extension

       "-m[no-]perf2-ext"
           Enable/Disable Performance extension 2

       "-m[no-]string-ext"
           Enable/Disable String extension

       "-m[no-]reduced-regs"
           Enable/Disable Reduced Register configuration (GPR16) option

       "-m[no-]audio-isa-ext"
           Enable/Disable AUDIO ISA extension

       "-m[no-]fpu-sp-ext"
           Enable/Disable FPU SP extension

       "-m[no-]fpu-dp-ext"
           Enable/Disable FPU DP extension

       "-m[no-]fpu-fma"
           Enable/Disable FPU fused-multiply-add instructions

       "-mall-ext"
           Turn on all extensions and instructions support

       The following options are available when as is configured for a PowerPC
       processor.

       -a32
           Generate ELF32 or XCOFF32.

       -a64
           Generate ELF64 or XCOFF64.

       -K PIC
           Set EF_PPC_RELOCATABLE_LIB in ELF flags.

       -mpwrx | -mpwr2
           Generate code for POWER/2 (RIOS2).

       -mpwr
           Generate code for POWER (RIOS1)

       -m601
           Generate code for PowerPC 601.

       -mppc, -mppc32, -m603, -m604
           Generate code for PowerPC 603/604.

       -m403, -m405
           Generate code for PowerPC 403/405.

       -m440
           Generate code for PowerPC 440.  BookE and some 405 instructions.

       -m464
           Generate code for PowerPC 464.

       -m476
           Generate code for PowerPC 476.

       -m7400, -m7410, -m7450, -m7455
           Generate code for PowerPC 7400/7410/7450/7455.

       -m750cl
           Generate code for PowerPC 750CL.

       -mppc64, -m620
           Generate code for PowerPC 620/625/630.

       -me500, -me500x2
           Generate code for Motorola e500 core complex.

       -me500mc
           Generate code for Freescale e500mc core complex.

       -me500mc64
           Generate code for Freescale e500mc64 core complex.

       -me5500
           Generate code for Freescale e5500 core complex.

       -me6500
           Generate code for Freescale e6500 core complex.

       -mspe
           Generate code for Motorola SPE instructions.

       -mtitan
           Generate code for AppliedMicro Titan core complex.

       -mppc64bridge
           Generate code for PowerPC 64, including bridge insns.

       -mbooke
           Generate code for 32-bit BookE.

       -ma2
           Generate code for A2 architecture.

       -me300
           Generate code for PowerPC e300 family.

       -maltivec
           Generate code for processors with AltiVec instructions.

       -mvle
           Generate code for Freescale PowerPC VLE instructions.

       -mvsx
           Generate code for processors with Vector-Scalar (VSX) instructions.

       -mhtm
           Generate code for processors with Hardware Transactional Memory
           instructions.

       -mpower4, -mpwr4
           Generate code for Power4 architecture.

       -mpower5, -mpwr5, -mpwr5x
           Generate code for Power5 architecture.

       -mpower6, -mpwr6
           Generate code for Power6 architecture.

       -mpower7, -mpwr7
           Generate code for Power7 architecture.

       -mpower8, -mpwr8
           Generate code for Power8 architecture.

       -mcell
       -mcell
           Generate code for Cell Broadband Engine architecture.

       -mcom
           Generate code Power/PowerPC common instructions.

       -many
           Generate code for any architecture (PWR/PWRX/PPC).

       -mregnames
           Allow symbolic names for registers.

       -mno-regnames
           Do not allow symbolic names for registers.

       -mrelocatable
           Support for GCC's -mrelocatable option.

       -mrelocatable-lib
           Support for GCC's -mrelocatable-lib option.

       -memb
           Set PPC_EMB bit in ELF flags.

       -mlittle, -mlittle-endian, -le
           Generate code for a little endian machine.

       -mbig, -mbig-endian, -be
           Generate code for a big endian machine.

       -msolaris
           Generate code for Solaris.

       -mno-solaris
           Do not generate code for Solaris.

       -nops=count
           If an alignment directive inserts more than count nops, put a
           branch at the beginning to skip execution of the nops.

       See the info pages for documentation of the RX-specific options.

       The following options are available when as is configured for the s390
       processor family.

       -m31
       -m64
           Select the word size, either 31/32 bits or 64 bits.

       -mesa
       -mzarch
           Select the architecture mode, either the Enterprise System
           Architecture (esa) or the z/Architecture mode (zarch).

       -march=processor
           Specify which s390 processor variant is the target, g6, g6, z900,
           z990, z9-109, z9-ec, z10, z196, or zEC12.

       -mregnames
       -mno-regnames
           Allow or disallow symbolic names for registers.

       -mwarn-areg-zero
           Warn whenever the operand for a base or index register has been
           specified but evaluates to zero.

       The following options are available when as is configured for a
       TMS320C6000 processor.

       -march=arch
           Enable (only) instructions from architecture arch.  By default, all
           instructions are permitted.

           The following values of arch are accepted: "c62x", "c64x", "c64x+",
           "c67x", "c67x+", "c674x".

       -mdsbt
       -mno-dsbt
           The -mdsbt option causes the assembler to generate the
           "Tag_ABI_DSBT" attribute with a value of 1, indicating that the
           code is using DSBT addressing.  The -mno-dsbt option, the default,
           causes the tag to have a value of 0, indicating that the code does
           not use DSBT addressing.  The linker will emit a warning if objects
           of different type (DSBT and non-DSBT) are linked together.

       -mpid=no
       -mpid=near
       -mpid=far
           The -mpid= option causes the assembler to generate the
           "Tag_ABI_PID" attribute with a value indicating the form of data
           addressing used by the code.  -mpid=no, the default, indicates
           position-dependent data addressing, -mpid=near indicates position-
           independent addressing with GOT accesses using near DP addressing,
           and -mpid=far indicates position-independent addressing with GOT
           accesses using far DP addressing.  The linker will emit a warning
           if objects built with different settings of this option are linked
           together.

       -mpic
       -mno-pic
           The -mpic option causes the assembler to generate the "Tag_ABI_PIC"
           attribute with a value of 1, indicating that the code is using
           position-independent code addressing,  The "-mno-pic" option, the
           default, causes the tag to have a value of 0, indicating position-
           dependent code addressing.  The linker will emit a warning if
           objects of different type (position-dependent and position-
           independent) are linked together.

       -mbig-endian
       -mlittle-endian
           Generate code for the specified endianness.  The default is little-
           endian.

       The following options are available when as is configured for a TILE-Gx
       processor.

       -m32 | -m64
           Select the word size, either 32 bits or 64 bits.

       -EB | -EL
           Select the endianness, either big-endian (-EB) or little-endian
           (-EL).

       The following options are available when as is configured for an Xtensa
       processor.

       --text-section-literals | --no-text-section-literals
           Control the treatment of literal pools.  The default is
           --no-text-section-literals, which places literals in separate
           sections in the output file.  This allows the literal pool to be
           placed in a data RAM/ROM.  With --text-section-literals, the
           literals are interspersed in the text section in order to keep them
           as close as possible to their references.  This may be necessary
           for large assembly files, where the literals would otherwise be out
           of range of the "L32R" instructions in the text section.  These
           options only affect literals referenced via PC-relative "L32R"
           instructions; literals for absolute mode "L32R" instructions are
           handled separately.

       --absolute-literals | --no-absolute-literals
           Indicate to the assembler whether "L32R" instructions use absolute
           or PC-relative addressing.  If the processor includes the absolute
           addressing option, the default is to use absolute "L32R"
           relocations.  Otherwise, only the PC-relative "L32R" relocations
           can be used.

       --target-align | --no-target-align
           Enable or disable automatic alignment to reduce branch penalties at
           some expense in code size.    This optimization is enabled by
           default.  Note that the assembler will always align instructions
           like "LOOP" that have fixed alignment requirements.

       --longcalls | --no-longcalls
           Enable or disable transformation of call instructions to allow
           calls across a greater range of addresses.    This option should be
           used when call targets can potentially be out of range.  It may
           degrade both code size and performance, but the linker can
           generally optimize away the unnecessary overhead when a call ends
           up within range.  The default is --no-longcalls.

       --transform | --no-transform
           Enable or disable all assembler transformations of Xtensa
           instructions, including both relaxation and optimization.  The
           default is --transform; --no-transform should only be used in the
           rare cases when the instructions must be exactly as specified in
           the assembly source.  Using --no-transform causes out of range
           instruction operands to be errors.

       --rename-section oldname=newname
           Rename the oldname section to newname.  This option can be used
           multiple times to rename multiple sections.

       --trampolines | --no-trampolines
           Enable or disable transformation of jump instructions to allow
           jumps across a greater range of addresses.    This option should be
           used when jump targets can potentially be out of range.  In the
           absence of such jumps this option does not affect code size or
           performance.  The default is --trampolines.

       The following options are available when as is configured for a Z80
       family processor.

       -z80
           Assemble for Z80 processor.

       -r800
           Assemble for R800 processor.

       -ignore-undocumented-instructions
       -Wnud
           Assemble undocumented Z80 instructions that also work on R800
           without warning.

       -ignore-unportable-instructions
       -Wnup
           Assemble all undocumented Z80 instructions without warning.

       -warn-undocumented-instructions
       -Wud
           Issue a warning for undocumented Z80 instructions that also work on
           R800.

       -warn-unportable-instructions
       -Wup
           Issue a warning for undocumented Z80 instructions that do not work
           on R800.

       -forbid-undocumented-instructions
       -Fud
           Treat all undocumented instructions as errors.

       -forbid-unportable-instructions
       -Fup
           Treat undocumented Z80 instructions that do not work on R800 as
           errors.

SEE ALSO
       gcc(1), ld(1), and the Info entries for binutils and ld.

COPYRIGHT
       Copyright (c) 1991-2014 Free Software Foundation, Inc.

       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is included in the section entitled "GNU
       Free Documentation License".



binutils-2.25-system              2015-02-25                             AS(1)
