


lib::B::C(3p)    Perl Programmers Reference Guide   lib::B::C(3p)


NAME
       B::C - Perl compiler's C backend

SYNOPSIS
               perl -MO=C[,OPTIONS] foo.pl


DESCRIPTION
       This compiler backend takes Perl source and generates C
       source code corresponding to the internal structures that
       perl uses to run your program. When the generated C source
       is compiled and run, it cuts out the time which perl would
       have taken to load and parse your program into its
       internal semi-compiled form. That means that compiling
       with this backend will not help improve the runtime
       execution speed of your program but may improve the start-
       up time.  Depending on the environment in which your
       program runs this may be either a help or a hindrance.

OPTIONS
       If there are any non-option arguments, they are taken to
       be names of objects to be saved (probably doesn't work
       properly yet).  Without extra arguments, it saves the main
       program.

       -ofilename
           Output to filename instead of STDOUT

       -v  Verbose compilation (currently gives a few compilation
           statistics).

       --  Force end of options

       -uPackname
           Force apparently unused subs from package Packname to
           be compiled.  This allows programs to use eval "foo()"
           even when sub foo is never seen to be used at compile
           time. The down side is that any subs which really are
           never used also have code generated. This option is
           necessary, for example, if you have a signal handler
           foo which you initialise with $SIG{BAR} = "foo".  A
           better fix, though, is just to change it to $SIG{BAR}
           = \&foo. You can have multiple -u options. The
           compiler tries to figure out which packages may
           possibly have subs in which need compiling but the
           current version doesn't do it very well. In
           particular, it is confused by nested packages (i.e.
           of the form A::B) where package A does not contain any
           subs.

       -D  Debug options (concatenated or separate flags like
           perl -D).





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lib::B::C(3p)    Perl Programmers Reference Guide   lib::B::C(3p)


       -Do OPs, prints each OP as it's processed

       -Dc COPs, prints COPs as processed (incl. file & line num)

       -DA prints AV information on saving

       -DC prints CV information on saving

       -DM prints MAGIC information on saving

       -f  Force optimisations on or off one at a time.

       -fcog
           Copy-on-grow: PVs declared and initialised statically.

       -fno-cog
           No copy-on-grow.

       -On Optimisation level (n = 0, 1, 2, ...). -O means -O1.
           Currently, -O1 and higher set -fcog.

EXAMPLES
           perl -MO=C,-ofoo.c foo.pl
           perl cc_harness -o foo foo.c

       Note that cc_harness lives in the B subdirectory of your
       perl library directory. The utility called perlcc may also
       be used to help make use of this compiler.

           perl -MO=C,-v,-DcA bar.pl > /dev/null


BUGS
       Plenty. Current status: experimental.

AUTHOR
       Malcolm Beattie, mbeattie@sable.ox.ac.uk




















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lib::B::C(3p)    Perl Programmers Reference Guide   lib::B::C(3p)



























































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