# 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 those leading tabs
# reset
_DEC_uname_r=
_DEC_cc_style=
# set
_DEC_uname_r=`uname -r`
# _DEC_cc_style set soon below
# Configure Black Magic (TM)
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' ;;
old) optimize='-O2 -Olimit 3200' ;;
esac
ccflags="$ccflags -D_INTRINSICS"
;;
esac
;;
esac
# 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 $libswanted | sed -e 's/ ndbm / /'`"
# the basic lddlflags used always
lddlflags='-shared -expect_unresolved "*"'
# Fancy compiler suites use optimising linker as well as compiler.
# <spider@Orb.Nashua.NH.US>
case "$_DEC_uname_r" in
*[123].*) # old loader
lddlflags="$lddlflags -O3"
;;
*) lddlflags="$lddlflags $optimize -msym"
# -msym: If using a sufficiently recent /sbin/loader,
# keep the module symbols with the modules.
;;
esac
# Yes, the above loses if gcc does not use the system linker.
# If that happens, let me know about it. <jhi@iki.fi>
# If debugging or (old systems and doing shared)
# then do not strip the lib, otherwise, strip.
# As noted above the -DDEBUGGING is added automagically by Configure if -g.
case "$optimize" in
*-g*) ;; # left intentionally blank
*) case "$_DEC_uname_r" in
*[123].*)
case "$useshrplib" in
false|undef|'') lddlflags="$lddlflags -s" ;;
esac
;;
*) lddlflags="$lddlflags -s"
;;
esac
;;
esac
#
# Unset temporary variables no more needed.
#
unset _DEC_cc_style
unset _DEC_uname_r
#
# History:
#
# 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.
#