NAME

cw - invoke one or more compilers with argument translation

SYNOPSIS

cw {-_cc|-_gcc|-_CC|-_g++} [options] [compiler args...]

DESCRIPTION

cw is a facility for invoking one or more compilers, providing translation from Sun Studio arguments as appropriate. This allows the use of arbitrary compilers without the need to alter large numbers of makefiles. A mode called shadow compilation, the default, invokes two different compilers so that warnings and errors may be obtained from both. See SHADOW COMPILATION for details. This version of cw supports Sun Studio 10 and 11 and gcc 3.4.3 as shipped in Solaris.

ARGUMENTS

Exactly one of the following arguments is required, and must appear immediately following cw in the argument list:

-_cc

Select Sun Studio C (cc) as the primary compiler.

-_gcc

Select GNU C (gcc) as the primary compiler.

-_CC

Select Sun Studio C++ (CC) as the primary compiler.

-_g++

Select GNU C++ (g++) as the primary compiler.

OPTIONS

The following options are supported:

-_compiler

Do not invoke any compiler; instead, write to standard output the full path to the primary compiler that would be invoked. If this option is given, it must appear immediately following the compiler selection argument, and all other options will be disregarded.

-_versions

Print the cw version, followed in turn by the path to and versions of each compiler which would be invoked. If this option is given, it must appear immediately following the compiler selection argument, and all other options will be disregarded.

-_noecho

Normally, cw writes to standard error the actual compiler commands invoked, each prefixed with '+'. This option suppresses these messages.

-_cc=,-_gcc=,-_CC=,-g++=

Pass compiler-dependent options. See ARGUMENT TRANSLATION.

SHADOW COMPILATION

Unless otherwise directed by environment variables (see ENVIRONMENT), cw will invoke both the compiler specified by its first argument (primary) and a designated alternate compiler (shadow). The primary compiler will be invoked with the arguments given to cw, translated as described in ARGUMENT TRANSLATION. The secondary compiler will be invoked in parallel with the primary (but see ENVIRONMENT); its arguments will likewise be translated. However, the shadow compiler's arguments will also be modified as follows:

1.

If none of -c, -E, -P, or -S appears in the argument list (that is, linking is attempted), the shadow compiler will not be invoked. This is because the objects built with that compiler which would be linked have been previously discarded.

2.

If an option of the form -ofilename was provided, it will be replaced by two options of the form -o tempfile.

3.

If the option -o was provided, its following argument will be replaced by tempfile.

4.

If neither of the above options was provided, two options of the form -o tempfile will be added to the end of the argument list used to invoke the shadow compiler.

In all three cases, tempfile is the name of a temporary file which will be removed by cw before it terminates.

When shadow compilation is in effect, cw writes to standard error each compiler's standard error output following its argument list. Messages from the two 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, and the secondary compiler's standard output will be discarded.

Because the Studio 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

The arguments provided to cw will be passed through to each compiler invoked, altered as follows:

1.

Options intended for cw itself are removed.

2.

The shadow compiler's arguments are modified as described in SHADOW COMPILATION so that its output is discarded.

3.

If the compiler to be invoked is a GNU 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. Arguments which begin with -_gcc= or -_g++= will be passed in place with the leading portion removed. Arguments which begin with -_cc= or -_CC= will be discarded. See the comments at the head of usr/src/tools/cw/cw.c for a detailed list of translations.

4.

If the compiler to be invoked is a Studio C or C++ compiler, the remaining arguments are passed unmodified and in the same order as given to cw. Arguments which begin with -_cc= or -_CC= will be passed in place with the leading portion removed. Arguments which begin with -_gcc= or -_g++= will be discarded.

ENVIRONMENT

CW_NO_SHADOW

If this variable is set in the environment, invoke only the primary compiler.

CW_SHADOW_SERIAL

If this variable is set in the environment, invoke the primary compiler, wait for it to complete, then invoke the shadow compiler. Normally the two compilers are invoked in parallel. If CW_NO_SHADOW is set, this has no effect.

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.

CW_CC, CW_CPLUSPLUS

If these variables are set in the environment, they specify the full pathname for the Studio C and C++ compilers, respectively.

CW_CC_DIR, CW_CPLUSPLUS_DIR, SPRO_VROOT, SPRO_ROOT, BUILD_TOOLS

If CW_CC or CW_CPLUSPLUS are not set, these variables define the search path for Studio compilers as follows: If CW_CC_DIR is set, the Studio C compiler in $CW_CC_DIR will be used. Likewise, if CW_CPLUSPLUS_DIR is set, the Studio C++ compiler in $CW_CPLUSPLUS_DIR will be used. Otherwise, if SPRO_VROOT is set, the Studio C and C++ compilers in $SPRO_VROOT/bin will be used. Otherwise, if SPRO_ROOT is set, the Studio C and C++ compilers in $SPRO_ROOT/SS12/bin will be used. Otherwise, if BUILD_TOOLS is set, the Studio C and C++ compilers in $BUILD_TOOLS/SUNWspro/SS12/bin will be used. Otherwise, the Studio compilers in a predefined default location will be used.

CW_GCC, CW_GPLUSPLUS

If these variables are set in the environment, they specify the full pathname for the GNU C and C++ compilers, respectively.

CW_GCC_DIR, CW_GPLUSPLUS_DIR, GNU_ROOT

If CW_GCC or CW_GPLUSPLUS are not set, these variables alter the search path for GNU compilers in a manner similar to that described above for the Studio compilers. Specifically: If CW_GCC_DIR is set, the GNU C compiler in $CW_GCC_DIR will be used. Likewise, if CW_GPLUSPLUS_DIR is set, the GNU C++ compiler in $CW_GPLUSPLUS_DIR will be used. Otherwise, if GNU_ROOT is set, the GNU C and C++ compilers in $GCC_ROOT/bin will be used. Otherwise, the GNU compilers in a predefined default location will be used.

EXIT STATUS

The following exit status values are returned:

0

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

>0

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

BUGS

The translations provided for gcc are not always exact and in some cases reflect local ON policy rather than actual equivalence.

Additional compiler types should be supported.

The translation engine is hacky.

SEE ALSO

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