[p5sagit/p5-mst-13.2.git] / hints / dec_osf.sh

# hints/dec_osf.sh

#       * If you want to debug perl or want to send a
#       stack trace for inclusion into an bug report, call
#       Configure with the additional argument  -Doptimize=-g2
#       or uncomment this assignment to "optimize":
#
#optimize=-g2
#
#       If you want both to optimise and debug with the DEC cc
#       you must have -g3, e.g. "-O4 -g3", and (re)run Configure.
#
#       * gcc can always have both -g and optimisation on.
#
#       * debugging optimised code, no matter what compiler
#       one is using, can be surprising and confusing because of
#       the optimisation tricks like code motion, code removal,
#       loop unrolling, and inlining. The source code and the
#       executable code simply do not agree any more while in
#       mid-execution, the optimiser only cares about the results.
#
#       * Configure will automatically add the often quoted
#       -DDEBUGGING for you if the -g is specified.
#
#       * There is even more optimisation available in the new
#       (GEM) DEC cc: -O5 and -fast. "man cc" will tell more about them.
#       The jury is still out whether either or neither help for Perl
#       and how much. Based on very quick testing, -fast boosts
#       raw data copy by about 5-15% (-fast brings in, among other
#       things, inlined, ahem, fast memcpy()), while on the other
#       hand searching things (index, m//, s///), seems to get slower.
#       Your mileage will vary.
#
#       * The -std is needed because the following compiled
#       without the -std and linked with -lm
#
#       #include <math.h>
#       #include <stdio.h>
#       int main(){short x=10,y=sqrt(x);printf("%d\n",y);}
#
#       will in Digital UNIX 3.* and 4.0b print 0 -- and in Digital
#       UNIX 4.0{,a} dump core: Floating point exception in the printf(),
#       the y has become a signaling NaN.
#
#       * Compilation warnings like:
#
#       "Undefined the ANSI standard macro ..."
#
#       can be ignored, at least while compiling the POSIX extension
#       and especially if using the sfio (the latter is not a standard
#       part of Perl, never mind if it says little to you).
#

# If using the DEC compiler we must find out the DEC compiler style:
# the style changed between Digital UNIX (aka DEC OSF/1) 3 and
# Digital UNIX 4. The old compiler was originally from Ultrix and
# the MIPS company, the new compiler is originally from the VAX world
# and it is called GEM. Many of the options we are going to use depend
# on the compiler style.

# do NOT, I repeat, *NOT* take away the leading tabs
# Configure Black Magic (TM)
        # reset
        _DEC_cc_style=
case "$cc" in
*gcc*)  ;; # pass
*)      # compile something small: taint.c is fine for this.
        # the main point is the '-v' flag of 'cc'.
        case "`cc -v -I. -c taint.c -o /tmp/taint$$.o 2>&1`" in
        */gemc_cc*)     # we have the new DEC GEM CC
                        _DEC_cc_style=new
                        ;;
        *)              # we have the old MIPS CC
                        _DEC_cc_style=old
                        ;;
        esac
        # cleanup
        rm -f /tmp/taint$$.o
        ;;
esac

# be nauseatingly ANSI
case "$cc" in
*gcc*)  ccflags="$ccflags -ansi"
        ;;
*)      ccflags="$ccflags -std"
        ;;
esac

# for gcc the Configure knows about the -fpic:
# position-independent code for dynamic loading

# we want optimisation

case "$optimize" in
'')     case "$cc" in 
        *gcc*)  
                optimize='-O3'                          ;;
        *)      case "$_DEC_cc_style" in
                new)    optimize='-O4'
                        ccflags="$ccflags -fprm d -ieee"
                        ;;
                old)    optimize='-O2 -Olimit 3200'     ;;
                esac
                ccflags="$ccflags -D_INTRINSICS"
                ;;
        esac
        ;;
esac

# Make glibpth agree with the compiler suite.  Note that /shlib
# is not here.  That's on purpose.  Even though that's where libc
# really lives from V4.0 on, the linker (and /sbin/loader) won't
# look there by default.  The sharable /sbin utilities were all
# built with "-Wl,-rpath,/shlib" to get around that.  This makes
# no attempt to figure out the additional location(s) searched by
# gcc, since not all versions of gcc are easily coerced into
# revealing that information.
glibpth="/usr/shlib /usr/ccs/lib /usr/lib/cmplrs/cc"
glibpth="$glibpth /usr/lib /usr/local/lib /var/shlib"

# dlopen() is in libc
libswanted="`echo $libswanted | sed -e 's/ dl / /'`"

# libPW contains nothing useful for perl
libswanted="`echo $libswanted | sed -e 's/ PW / /'`"

# libnet contains nothing useful for perl here, and doesn't work
libswanted="`echo $libswanted | sed -e 's/ net / /'`"

# libbsd contains nothing used by perl that is not already in libc
libswanted="`echo $libswanted | sed -e 's/ bsd / /'`"

# libc need not be separately listed
libswanted="`echo $libswanted | sed -e 's/ c / /'`"

# ndbm is already in libc
libswanted="`echo $libswanted | sed -e 's/ ndbm / /'`"

# the basic lddlflags used always
lddlflags='-shared -expect_unresolved "*"'

# Fancy compiler suites use optimising linker as well as compiler.
# <spider@Orb.Nashua.NH.US>
case "`uname -r`" in
*[123].*)       # old loader
                lddlflags="$lddlflags -O3"
                ;;
*)            if $test "X$optimize" = "X$undef"; then
                      lddlflags="$lddlflags -msym"
              else
                      lddlflags="$lddlflags $optimize -msym"
              fi
                # -msym: If using a sufficiently recent /sbin/loader,
                # keep the module symbols with the modules.
                ;;
esac
# Yes, the above loses if gcc does not use the system linker.
# If that happens, let me know about it. <jhi@iki.fi>


# If debugging or (old systems and doing shared)
# then do not strip the lib, otherwise, strip.
# As noted above the -DDEBUGGING is added automagically by Configure if -g.
case "$optimize" in
        *-g*) ;; # left intentionally blank
*)      case "`uname -r`" in
        *[123].*)
                case "$useshrplib" in
                false|undef|'') lddlflags="$lddlflags -s"       ;;
                esac
                ;;
        *) lddlflags="$lddlflags -s"
                ;;
        esac
        ;;
esac

#
# Make embedding in things like INN and Apache more memory friendly.
# Keep it overridable on the Configure command line, though, so that
# "-Uuseshrplib" prevents this default.
#

case "$_DEC_cc_style.$useshrplib" in
        new.)   useshrplib="$define"    ;;
esac

# The EFF_ONLY_OK from <sys/access.h> is present but dysfunctional for
# [RWX]_OK as of Digital UNIX 4.0[A-D]?.  If and when this gets fixed,
# please adjust this appropriately.  See also pp_sys.c just before the
# emulate_eaccess().

pp_sys_cflags='ccflags="$ccflags -DNO_EFF_ONLY_OK"'

# This script UU/usethreads.cbu will get 'called-back' by Configure 
# after it has prompted the user for whether to use threads.
cat > UU/usethreads.cbu <<'EOCBU'
case "$usethreads" in
$define|true|[yY]*)
        # Threads interfaces and flags changed with V4.0.
        case "`uname -r`" in
        *[123].*)
            libswanted="$libswanted pthreads mach exc c_r"
            ccflags="-threads $ccflags"
            ;;
        *)
            libswanted="$libswanted pthread exc"
            ccflags="-pthread $ccflags"
            ;;
        esac
        ccflags="-D_REENTRANT $ccflags"
        usemymalloc='n'
        ;;
esac
EOCBU

#
# Unset temporary variables no more needed.
#

unset _DEC_cc_style
    
#
# History:
#
# perl5.005_51:
#
#       September-1998 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * Added the -DNO_EFF_ONLY_OK flag ('use filetest;' support).
#
# perl5.004_57:
#
#       19-Dec-1997 Spider Boardman <spider@Orb.Nashua.NH.US>
#
#       * Newer Digital UNIX compilers enforce signaling for NaN without
#         -ieee.  Added -fprm d at the same time since it's friendlier for
#         embedding.
#
#       * Fixed the library search path to match cc, ld, and /sbin/loader.
#
#       * Default to building -Duseshrplib on newer systems.  -Uuseshrplib
#         still overrides.
#
#       * Fix -pthread additions for useshrplib.  ld has no -pthread option.
#
#
# perl5.004_04:
#
#       19-Sep-1997 Spider Boardman <spider@Orb.Nashua.NH.US>
#
#       * libnet on Digital UNIX is for JAVA, not for sockets.
#
#
# perl5.003_28:
#
#       22-Feb-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * Restructuring Spider's suggestions.
#
#       * Older Digital UNIXes cannot handle -Olimit ... for $lddlflags.
#       
#       * ld -s cannot be used in older Digital UNIXes when doing shared.
#
#
#       21-Feb-1997 Spider Boardman <spider@Orb.Nashua.NH.US>
#
#       * -hidden removed.
#       
#       * -DSTANDARD_C removed.
#
#       * -D_INTRINSICS added. (that -fast does not seem to buy much confirmed)
#
#       * odbm not in libc, only ndbm. Therefore dbm back to $libswanted.
#
#       * -msym for the newer runtime loaders.
#
#       * $optimize also in $lddflags.
#
#
# perl5.003_27:
#
#       18-Feb-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * unset _DEC_cc_style and more commentary on -std.
#
#
# perl5.003_26:
#
#       15-Feb-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * -std and -ansi.
#
#
# perl5.003_24:
#
#       30-Jan-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * Fixing the note on -DDEBUGGING.
#
#       * Note on -O5 -fast.
#
#
# perl5.003_23:
#
#       26-Jan-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * Notes on how to do both optimisation and debugging.
#
#
#       25-Jan-1997 Jarkko Hietaniemi <jhi@iki.fi>
#
#       * Remove unneeded libraries from $libswanted: PW, bsd, c, dbm
#
#       * Restructure the $lddlflags build.
#
#       * $optimize based on which compiler we have.
#
#
# perl5.003_22:
#
#       23-Jan-1997 Achim Bohnet <ach@rosat.mpe-garching.mpg.de>
#
#       * Added comments 'how to create a debugging version of perl'
#
#       * Fixed logic of this script to prevent stripping of shared
#         objects by the loader (see ld man page for -s) is debugging
#         is set via the -g switch.
#
#
#       21-Jan-1997 Achim Bohnet <ach@rosat.mpe-garching.mpg.de>
#
#       * now 'dl' is always removed from libswanted. Not only if
#         optimize is an empty string.
#        
#
#       17-Jan-1997 Achim Bohnet <ach@rosat.mpe-garching.mpg.de>
#
#       * Removed 'dl' from libswanted: When the FreePort binary
#         translator for Sun binaries is installed Configure concludes
#         that it should use libdl.x.yz.fpx.so :-(
#         Because the dlopen, dlclose,... calls are in the
#         C library it not necessary at all to check for the
#         dl library.  Therefore dl is removed from libswanted.
#       
#
#       1-Jan-1997 Achim Bohnet <ach@rosat.mpe-garching.mpg.de>
#       
#       * Set -Olimit to 3200 because perl_yylex.c got too big
#         for the optimizer.
#