NAME

cw — invoke one or more compilers with argument translation

SYNOPSIS

cw	[-C] [--versions] [--noecho] --primary compiler [--shadow compiler ...] -- compiler args ...

DESCRIPTION

cw is a facility for invoking one or more compilers, providing translation from Sun style arguments as appropriate. This allows the use of arbitrary compilers without the need to alter large numbers of makefiles. A mode called shadow compilation invokes multiple compilers so that warnings and errors may be obtained from both. See SHADOW COMPILATION for details. This version of cw supports compilers with both Sun Studio 12 and GCC-style command lines.

ARGUMENTS

Both the --primary and --shadow parameters take a compiler specification. This is a comma-separated list of the form name,executable,style Where name is a name for the compiler, executable is the full path to the compiler executable, and style is the style of command-line options the compiler expects, either sun or gnu.

 

 

--primary compiler

Specify the compiler to be used primarily (that which is used for link-editing and pre-processing, and whos objects we deliver).

 

 

--shadow compiler

Specify a shadow compiler, which builds sources for the sake of checking code quality and compatibility, but has its output discarded.

 

 

--noecho

Do not echo the actual command line of any compilers invoked.

 

 

--versions

Request from each configured primary and shadow compiler its version information.

 

 

-C

The sources being compiled are C++. This is necessary as it affects the translation of compiler arguments.

 

 

--

Arguments intended for the compilers themselves must be separated from those of cw by a --.

 

 

-_name=

 

-_style=

Parameters intended for the compiler be guarded with options of the form -_name= and -_style= Where name and style are those passed to --primary and --shadow this allows certain flags to be passed only to certain classes of compiler.

For historical reasons, the -_style= option is also translated such that a style of sun may use the flag -_cc= and a style of gnu may use the flag -_gcc=, and when the -C option is given and C++ is in use the style of sun may use the flag -_CC= and the style of gnu may use the flag -_g++=.

SHADOW COMPILATION

If --shadow compilers are specified cw will invoke shadow compiler, with the outputs modified (as well as any translation for compiler style) as follows:

1. If neither of -c, -S appears in the argument list (that is, linking is attempted or only the pre-processor is invoked), the shadow compilers will not be invoked.
2. If the -o filename option was provided, with or without a separating space, it will be replaced with -o tempfile
3. If the option -o was not provided, -o tempfile will be added to the end of the argument list used to invoke the shadow compilers.

When shadow compilation is in effect, cw writes to standard error each compiler's standard error output following its argument list. Messages from the compilers will not be interleaved. If cw is used to invoke the preprocessor and no output location is specified, cw will write to standard output the primary compiler's standard output. Because the Sun compilers write intermediate objects to fixed filenames in the current directory when instructed to compile and link multiple source files via a single command line, it would be unsafe to invoke more than one compiler in this fashion. Therefore cw does not accept multiple source files unless the preprocessor is to be invoked. An attempt to invoke cw in this manner will result in an error.

ARGUMENT TRANSLATION

If the compiler to be invoked is a GNU-style C or C++ compiler, a set of default flags is added to the beginning of the argument list, and the remaining arguments are translated to their closest appropriate semantic equivalents and passed in the same order as their counterparts given to cw. See the comments at the head of usr/src/tools/cw/cw.c for a detailed list of translations.

ENVIRONMENT

 

 

CW_SHADOW_SERIAL

If this variable is set in the environment, invoke the primary compiler, wait for it to complete, then invoke the shadow compilers. Normally the primary and shadow compilers are invoked in parallel.

 

 

CW_NO_EXEC

If this variable is set in the environment, write the usual output to standard error but do not actually invoke any compiler. This is useful for debugging the translation engine.

EXIT STATUS

The following exit status values are returned:

 

 

0

The primary compiler, and shadow compilers if invoked, both completed successfully.

 

 

>0

A usage error occurred, or one or more compilers returned a nonzero exit status.

SEE ALSO

cc(1), CC(1), gcc(1)

BUGS

The translations provided for gcc are not always exact and in some cases reflect local policy rather than actual equivalence. Additional compiler types should be supported. The translation engine is hacky.