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C Set ++ for AIX Compiler Options



  C Set ++ for AIX Compiler

  Usage:
     xlC [ option | inputfile ]...
     xlc [ option | inputfile ]...
     cc [ option | inputfile ]...
     c89 [ option | inputfile ]...
     icc [ option | inputfile ]...
     ixlc [ option | inputfile ]...
     ic89 [ option | inputfile ]...

  Description:
     The xlC and related commands compile C and C++ source files.
     They also processes assembler source files and object files. Unless the
     -c option is specified, xlC calls the linkage editor to produce a
     single object file. Input files may be any of the following:
       1. file name with .C suffix: C++ source file
       2. file name with .i suffix: preprocessed C or C++ source file
       3. file name with .c suffix: C source file
       4. file name with .o suffix: object file for ld command
       5. file name with .s suffix: assembler source file

  Options:
     Options can be flag options or keyword options:

       1. Flag options:

        -#        Display language processing commands but do
                  not invoke them; output goes to stdout.
        -+        Treat .c files as C++ source code.
        -a        Produce test coverage information; output goes to .d file.
        -ae       Produce test coverage information, expecting C++
                  exception handling to disrupt the normal flow of
                  control; output goes to .d file.
        -B{prefix}
                  Construct alternate compiler/assembler/linkage editor
                  program names. {prefix} is added to the beginning of
                  the standard program names.
        -c        Do not send object files to the linkage editor.
        -C        Write comments to output when doing preprocessing,
                  used with -E and -P.
        -D{name}[={def}]
                  Define {name} as in #define directive. If {def} is
                  not specified, 1 is assumed.
        -E        Preprocess but do not compile; output goes to stdout
        -F{x}[:{stanza}]
                  Use alternate configuration file {x} with optional
                  {stanza}. If {stanza} is not specified, xlC is
                  assumed.
        -g        Produce information for the debugger.
        -I{dir}   Search in directory {dir} for include files that
                  do not start with an absolute path.
        -l{key}   Search the specified library file,
                  where {key} selects the file lib{key}.a.
        -L{dir}   Search in directory {dir} for files specified by -l{key}.
        -ma       Generate inline calls to the "alloca" function as if
                  "#pragma alloca" directives were in the source file.
        -M        Generate information to be included in a "make"
                  description file; output goes to .u file.
        -o{name}  Name the executable file {name} instead of a.out.
                  When used with the -c option and one source file,
                  name the object file {name} instead of filename.o.
        -O        Optimize generated code.
        -O2       Equivalent level of optimization as -O in the
                  previous release.
        -O3       Perform some memory and compile time intensive
                  optimizations in addition to those executed with -O2.
                  The -O3 specific optimizations have the potential to
                  alter the semantics of a user's program.
                  The compiler guards against these optimizations at -O2
                  and the option -qstrict is provided at -O3 to turn off
                  these aggressive optimizations.
        -p        Generate profiling support code.
        -pg       Generate profiling support code including BSD
                  profiling support.
        -P        Preprocess but do not compile; output goes to .i file.
        -Q        (C++) Requests inlining of inline routines.
        -Q!       (C++) Turns off inlining.
        -Q{x}     (C) Inline all appropriate functions where x can be
                  one of the following:
                    !       Not inline any function
                    ={lc}   Inline if number of source statement in
                            function is less than the number specified
                            in {lc}.
                    -{nm}   Not inline function listed by names in {nm}
                    +{nm}   Attempt to inline function listed by names
                            in {nm}.
        -S        Produce a .s file for any source file processed by the
                  compiler.
        -t{x}     Apply prefix from the -B option to the specified program {x},
                  where x can be one or more of the following:
                    p = preprocessor
                    c = compiler frontend
                    b = compiler backend
                    i = compiler inliner
                    a = assembler
                    l = linkage editor.
                    m = 'munch' utility
                    f = C++ name demangler utility
                    I = inter procedural analysis
        -U{name}  Undefine name as in #undef directive.
        -v        Displays language processing commands as they
                  are invoked by xlC; output goes to stdout.
        -w        Suppress informational, language-level, and warning messages.
        -W{x,y}   Give the options {y} to the compiler program {x}
                  where x can be one or more of the following:
                    {p,c,b,i,a,l,I,m,f}
        -y{x}     Specify compile-time rounding of constant floating-point
                  expressions, where {x} can be one of the following:
                    n = round to nearest
                    m = round toward minus infinity
                    p = round toward positive infinity
                    z = round toward zero.

       2. Keyword options:

          Keyword options are specified in one of the following ways:

          -q{option}
          -q{option}={parameter}
          -q{option}={parameter}:{parameter}

          where {option} is an option name and {parameter} is a
          parameter value.
          Keyword options with no parameters represent switches
          that may be either on or off. The keyword by itself turns
          the switch on, and the keyword preceded by the letters NO
          turns the switch off. For example, -qLIST tells the
          compiler to produce a listing and -qNOLIST tells the
          compiler not to produce a listing. If an option that
          represents a switch is set more than once, the compiler
          uses the last setting.

          Keyword option and parameter names may appear in either
          UPPER CASE or lower case letters in the xlC command.


          Options without parameters:

          ansialias   Use type-based aliasing during optimization.
          attr        Produce an attribute listing containing only
                      referenced names; output goes to .lst file.
          browse      Produce information for the source code browser;
                      output goes to .brs file.
          check       Generate code to check for integer division by 0.
          compact     Reduce code size where possible, at the expense
                      of execution speed.  Code size is reduced by
                      inhibiting optimizations that replicate or expand
                      code inline.
          cpluscmt    (C only) Permit "//" to introduce a comment that lasts
                      until the end of the current source line, as in C++.
          dbcs        String literals and comments can contain DBCS
                      characters (same as mbcs option).
          dbxextra    Generate symbol table information for unreferenced
                      variables. By default such information is not generated
                      thus reducing the size of the executable compiled with
                      the "-g" option.
          digraph     Allow special digraph and keyword operators.
          dollar      Allow '$' as an identifier character
          extchk      Perform external name type-checking and function
                      call checking.
          flttrap     Generate instructions to trap floating-point exceptions.
          genpcomp[=dirname]
                      Generate pretokenized include files.  See C Set ++
                      User's Guide for details.
          hd          Generate additional information for use with the
                      HeapView Debugger
          idirfirst   Specify the search order for files included with
                      the #include "file_name" directive.  Use -qidirfist
                      with the -Idirectory option.  If -qidirfirst option
                      is specified, the directories specified by the
                      -Idirectory option are searched before the directory
                      where the current file resides.
          ignerrno    Tell the optimizer that the program will never refer to
                      or set errno.  This allows additional optimizations.
          info        Produce more warning and information messages for
                      possible problems in the program.
          inlglue     Generate fast external linkage by inlining the
                      code (pointer glue code) necessary at calls
                      via a function pointer and calls to external
                      procedures.
          libansi
          list        Produce an object listing; output goes to .lst file.
          listopt     Display the settings of all options; output goes
                      to .lst file.
          macpstr     Allow '\p' as the first character of a string constant
                      which will be replaced by the length in bytes.
          mbcs        String literals and comments can contain DBCS
                      characters (same as dbcs option).
          noprint     Direct listing to /dev/null.
          nostdinc    Specify which files are included with the #include
                      "file_name" and #include {file_name} directives.
                      If -qnostdinc is specified, the /usr/include (C) or
                      /usr/lpp/xlC/include (C++) directory is not searched.
          once         Only process each include file one time.  The default is
                      -qnoonce.
          pascal      Accept and ignore the keyword 'pascal' as a type modifier.
          phsinfo     Produce compiler phase information; output goes to stdout.
          proto       (C only) Assert that procedure call points agree
                      with their declarations even if the procedure has
                      not been prototyped. This allows the caller to
                      pass floating point arguments in floating point
                      registers instead of general purpose registers.
          ro          Put string literals in read only area.
          rwvftable   (C++ only) Place virtual function tables into
                      read/write memory.
          showinc     Include the source of all included files in the
                      source listing, if the SOURCE option is in effect.
          source      Produce a source listing; output goes to .lst file.
          srcmsg      Reconstruct source lines in error along with the
                      diagnostic messages in the stderr file.
          strict      Valid only at -O3.  This option turns off aggresive
                      optimizations which have the potential to alter the
                      semantics of a user's program. This option also sets
                      -qfloat=nofltint:norsqrt.
          tempinc     Automatically generate template functions in the
                      "tempinc" subdirectory. Use the "notempinc" option to
                      suppress this behaviour.
          tocdata     Place scalar external data of one word or less
                      in the TOC (Table of Contents).   If this option is not
                      on, the address of scalar external data is placed in the
                      TOC.  This requires an extra load of the address before
                      accessing the data.
          twolink     (C++ only) Link twice in order to minimize the number
                      of static constructors included from libraries (default
                      with langlvl=compat).
          unroll[=n]  Allow the optimizer to unroll loops.
          usepcomp[=dirname]
                      Use pretokenized include files.  See C Set ++ User's
                      Guide for details.
          vftable     (C++ only) Force virtual function tables to be generated
                      in this compilation unit.  The default is to define the
                      virtual function table for a class where the first
                      non-inline virtual member function is declared.  If
                      -qnovftable is specified, then no virtual function tables
                      are produced.
          xcall       Generate code to static routines within a compilation
                      unit as if they were external routines.
          xref        Produce a cross-reference listing containing
                      only referenced names.


     Options with parameters:

          align={algnopt}
                      Specify one of the following three alignment rules:
                      - POWER architecture (align=power, default)
                      - two byte alignment (align=twobyte)
                      - one byte alignment (align=packed)
                      for aligning C structs and unions. {algnopt} can be
                      one of: power, twobyte, or packed.
          arch={option}
                      Specifies the architecture on which the executable
                      program will be run.
                      The available options are:
                      com     Produce an object that contains instructions
                              that will run on all the POWER and PowerPC
                              hardware platforms.
                      pwr     Produce an object that contains instructions
                              that will run on the POWER hardware
                              platform.
                      pwr2    Produce an object that contains instructions
                              that will run on the POWER2 hardware
                              platform.
                      pwrx    Same as pwr2.
                      ppc     Produce an object that contains instructions
                              that will run on any of the 32-bit PowerPC
                              hardware platforms.
                      The default is -qarch=com.  If the -qarch option is
                      specified without the -qtune={option}, the compiler
                      uses -qtune=pwr.
          attr=full   Produce an attribute listing containing all names,
                      whether referenced or not; output goes to .lst file.
          cache=description
                      Describe the cache characteristics to the optimizer.
                      See C Set ++ User's Guide for details.
          chars=signed
          chars=unsigned
                      Specify whether the data type char will be signed
                      or unsigned.
          datalocal={name1}:{name2}: ...
                      Specify which data items are local.  If no names are
                      specified, all data items are assumed to be local.
          dataimported={name1}:{name2}: ...
                      Specify which data items are imported.  If no names are
                      specified, all data items are assumed to be imported.
                      This is the default.
          disjoint={disjointSpec}
                      Tell the optimizer that certain aliases are impossible.
                      See C Set ++ User's Guide for details.
          enum={enumopt}
                      Specify whether minimum-sized enumerated types will be
                      produced or not. {enumopt} can be either small or int.
                      small denotes that either one, two or four bytes of
                      storage will be allocated for enum variables based on
                      the range of the enum constants.
                      int is the default, and causes enum variables to be
                      treated as though they were of type (signed) int.
          flag={sev1}
                      Specify severity level of diagnostics to be reported
                      in source listing and stderr; the severity level
                      is one of {i,w,e,s,u}.
          flag={sev1}:{sev2}
                      Specify severity level of diagnostics to be reported
                      in source listing ({sev1}), and stderr ({sev2});
                      the severity levels are one of {i,w,e,s,u}.
          float={opt1}:{opt2}:...:{optN}
                      The available options are:
                      rndsngl  Ensure strict adherence to IEEE standard.
                               all operations on single-precision values
                               produce results that remain in single
                               precision.
                      hssngl   Round single-precision expressions only
                               when the results are stored into REAL*4 memory
                               locations.
                      nans     Detect conversion of single-precision NaNS to
                               double precision call checking.
                      hsflt    Never round single-precision expressions,
                               and don't perform range checking for
                               floating-point to integer conversions.
                      nomaf    Suppress generation of multiply-add
                               instructions.
                      nofold   Suppress compile-time evaluation of constant
                               floating-point expressions.
                      rrm      Specify run-time rounding mode. Compile with
                               this option if the run-time rounding mode
                               is round toward minus infinity, round toward
                               positive infinity, or not known.
                      rsqrt    Specify whether a division by the result of a
                               square root can be replaced with a multiply
                               by the reciprocal of the square root.
                               Default at -O2: -qfloat=norsqrt.
                               Default at -O3: -qfloat=rsqrt.
                      fltint   Specify whether range checking of floating
                               point to integer conversions is done.
                               Default at -O2: -qfloat=nofltint.
                               Default at -O3: -qfloat=fltint.
          flttrap={opt1}:{opt2}:...:{optN}
                      Generate instructions to detect and trap floating-point.
                      The available options are:  overflow, underflow,
                      zerodivide, invalid, inexact, enable, imprecise.
          halt={sev}  Stop compiler after first phase if severity of errors
                      detected equals or exceeds {sev}; the severity
                      level is one of i, w, e, s, u.
          ignprag=disjoint
          ignprag=isolated
          ignprag=all
                      Ignore the aliasing pragmas disjoint and/or isolated_call.
          initauto={hh}
                      Initialialize automatic storage to {hh}. {hh} is a
                      hexadecimal value.  This generates extra code and
                      should only be used for error determination.
          ipa[={ipa_options}]
                      Turn on inter procedural analysis.  See C Set ++
                      User's Guide for details.
          isolated_call={name1}:{name2}: ...
                      Specify that the calls to the functions listed have no
                      side effects. {name1} and {name2} are function names.
                      The user may specify as many function names as
                      necessary.
          langlvl={langlvl}
                      Specify language level to be used during compilation.
                      {langlvl} can be ansi, compat, or extended.
          maxmem={num}
                      Limit the amount of memory used by space intensive
                      optimizations to {num}.  {num} specified in kilobytes.
          priority=NNN
          proclocal={name1}:{name2}: ...
                      Specify which functions are local.
                      If no filenames are specified, all invoked functions
                      are assumed to be defined whithin the current file.
                      The last explicit specification for a function takes
                      precedence.
          procimported={name1}:{name2}: ...
                      Specify which functions are imported.  If no filenames
                      are specified, all invoked functions are assumed to be
                      defined outside the current file.  The last explicit
                      specification for a function takes precedence.
          procunknown={name1}:{name2}: ...
                      Specify which functions are unknown to be local or
                      imported.  If no filenames are specified, all functions
                      called are assumed to be unknown. This is the default
                      when no user options are specified. The last explicit
                      specification for a function takes precedence.
          spill={size}
                      Specify the size of the register allocation spill
                      area.
          tune={option}
                      Specifies the architecture system for which the
                      executable program is optimized.
                      The available options are:
                      601    Produce an object optimized for all the
                             PowerPC601 processors.
                      pwr    Produce an object optimized for the POWER
                             hardware platform.
                      pwr2   Produce an object optimized for the
                             POWER2 hardware platform.
                      pwrx   Same as pwr2.
          tempinc={directory}
                      Automatically generate template functions in the
                      specified directory. Use the "notempinc" option
                      to suppress this behaviour.
          tempmax={number}
                      Specify the maximum number of files to be created in
                      the tempinc directory for each template file.  The
                      default is 1.
          wait[={seconds}]
                      Specify the number of seconds to wait for a NetLS
                      license to become available.  The default is to wait
                      forever.
          xref=full   Produce a cross-reference listing containing
                      all names, whether referenced or not; output goes
                      to .lst file.

  For a detailed description of each option, please refer to the
  C Set ++ for AIX User's Guide.