1 CW(1ONBLD)                    illumos Build Tools                   CW(1ONBLD)
   2 
   3 NAME
   4      cw - invoke one or more compilers with argument translation
   5 
   6 SYNOPSIS
   7      cw [-C] [--versions] [--noecho] --primary compiler
   8         [--shadow compiler ...] -- compiler args ...
   9 
  10 DESCRIPTION
  11      cw is a facility for invoking one or more compilers, providing
  12      translation from Sun style arguments as appropriate.  This allows the use
  13      of arbitrary compilers without the need to alter large numbers of
  14      makefiles.  A mode called shadow compilation invokes multiple compilers
  15      so that warnings and errors may be obtained from both.  See SHADOW
  16      COMPILATION for details.  This version of cw supports compilers with both
  17      Sun Studio 12 and GCC-style command lines.
  18 
  19 ARGUMENTS
  20      Both the --primary and --shadow parameters take a compiler specification.
  21      This is a comma-separated list of the form name,executable,style Where
  22      name is a name for the compiler, executable is the full path to the
  23      compiler executable, and style is the style of command-line options the
  24      compiler expects, either sun or gnu.
  25 
  26      --primary compiler
  27              Specify the compiler to be used primarily (that which is used for
  28              link-editing and pre-processing, and whos objects we deliver).
  29 
  30      --shadow compiler
  31              Specify a shadow compiler, which builds sources for the sake of
  32              checking code quality and compatibility, but has its output
  33              discarded.
  34 
  35      --noecho
  36              Do not echo the actual command line of any compilers invoked.
  37 
  38      --versions
  39              Request from each configured primary and shadow compiler its
  40              version information.
  41 
  42      -C      The sources being compiled are C++.  This is necessary as it
  43              affects the translation of compiler arguments.
  44 
  45      --      Arguments intended for the compilers themselves must be separated
  46              from those of cw by a --.
  47 
  48      -_name=
  49 
  50      -_style=
  51              Parameters intended for the compiler be guarded with options of
  52              the form -_name= and -_style= Where name and style are those
  53              passed to --primary and --shadow this allows certain flags to be
  54              passed only to certain classes of compiler.
  55 
  56              For historical reasons, the -_style= option is also translated
  57              such that a style of sun may use the flag -_cc= and a style of
  58              gnu may use the flag -_gcc=, and when the -C option is given and
  59              C++ is in use the style of sun may use the flag -_CC= and the
  60              style of gnu may use the flag -_g++=.
  61 
  62 SHADOW COMPILATION
  63      If --shadow compilers are specified cw will invoke shadow compiler, with
  64      the outputs modified (as well as any translation for compiler style) as
  65      follows:
  66 
  67      1.   If neither of -c, -S appears in the argument list (that is, linking
  68           is attempted or only the pre-processor is invoked), the shadow
  69           compilers will not be invoked.
  70 
  71      2.   If the -o filename option was provided, with or without a separating
  72           space, it will be replaced with -o tempfile
  73 
  74      3.   If the option -o was not provided, -o tempfile will be added to the
  75           end of the argument list used to invoke the shadow compilers.
  76      When shadow compilation is in effect, cw writes to standard error each
  77      compiler's standard error output following its argument list.  Messages
  78      from the compilers will not be interleaved.  If cw is used to invoke the
  79      preprocessor and no output location is specified, cw will write to
  80      standard output the primary compiler's standard output.
  81 
  82      Because the Sun compilers write intermediate objects to fixed filenames
  83      in the current directory when instructed to compile and link multiple
  84      source files via a single command line, it would be unsafe to invoke more
  85      than one compiler in this fashion.  Therefore cw does not accept multiple
  86      source files unless the preprocessor is to be invoked.  An attempt to
  87      invoke cw in this manner will result in an error.
  88 
  89 ARGUMENT TRANSLATION
  90      If the compiler to be invoked is a GNU-style C or C++ compiler, a set of
  91      default flags is added to the beginning of the argument list, and the
  92      remaining arguments are translated to their closest appropriate semantic
  93      equivalents and passed in the same order as their counterparts given to
  94      cw.  See the comments at the head of usr/src/tools/cw/cw.c for a detailed
  95      list of translations.
  96 
  97 ENVIRONMENT
  98      CW_SHADOW_SERIAL
  99              If this variable is set in the environment, invoke the primary
 100              compiler, wait for it to complete, then invoke the shadow
 101              compilers.  Normally the primary and shadow compilers are invoked
 102              in parallel.
 103 
 104      CW_NO_EXEC
 105              If this variable is set in the environment, write the usual
 106              output to standard error but do not actually invoke any compiler.
 107              This is useful for debugging the translation engine.
 108 
 109 EXIT STATUS
 110      The following exit status values are returned:
 111 
 112      0       The primary compiler, and shadow compilers if invoked, both
 113              completed successfully.
 114 
 115      >0           A usage error occurred, or one or more compilers returned a
 116              nonzero exit status.
 117 
 118 SEE ALSO
 119      cc(1), CC(1), gcc(1)
 120 
 121 BUGS
 122      The translations provided for gcc are not always exact and in some cases
 123      reflect local policy rather than actual equivalence.
 124 
 125      Additional compiler types should be supported.
 126 
 127      The translation engine is hacky.
 128 
 129 illumos                        February 10, 2018                       illumos