source: trunk/essentials/dev-lang/perl/hints/linux.sh@ 3315

# hints/linux.sh
# Original version by rsanders
# Additional support by Kenneth Albanowski <[email protected]>
#
# ELF support by H.J. Lu <[email protected]>
# Additional info from Nigel Head <[email protected]>
# and Kenneth Albanowski <[email protected]>
#
# Consolidated by Andy Dougherty <[email protected]>
#
# Updated Thu Feb  8 11:56:10 EST 1996

# Updated Thu May 30 10:50:22 EDT 1996 by <[email protected]>

# Updated Fri Jun 21 11:07:54 EDT 1996
# NDBM support for ELF renabled by <[email protected]>

# No version of Linux supports setuid scripts.
d_suidsafe='undef'

# Debian and Red Hat, and perhaps other vendors, provide both runtime and
# development packages for some libraries.  The runtime packages contain shared
# libraries with version information in their names (e.g., libgdbm.so.1.7.3);
# the development packages supplement this with versionless shared libraries
# (e.g., libgdbm.so).
#
# If you want to link against such a library, you must install the development
# version of the package.
#
# These packages use a -dev naming convention in both Debian and Red Hat:
#   libgdbmg1  (non-development version of GNU libc 2-linked GDBM library)
#   libgdbmg1-dev (development version of GNU libc 2-linked GDBM library)
# So make sure that for any libraries you wish to link Perl with under
# Debian or Red Hat you have the -dev packages installed.
#
# Some operating systems (e.g., Solaris 2.6) will link to a versioned shared
# library implicitly.  For example, on Solaris, `ld foo.o -lgdbm' will find an
# appropriate version of libgdbm, if one is available; Linux, however, doesn't
# do the implicit mapping.
ignore_versioned_solibs='y'

# BSD compatibility library no longer needed
# 'kaffe' has a /usr/lib/libnet.so which is not at all relevant for perl.
# bind causes issues with several reentrant functions
set `echo X "$libswanted "| sed -e 's/ bsd / /' -e 's/ net / /' -e 's/ bind / /'`
shift
libswanted="$*"

# If you have glibc, then report the version for ./myconfig bug reporting.
# (Configure doesn't need to know the specific version since it just uses
# gcc to load the library for all tests.)
# We don't use __GLIBC__ and  __GLIBC_MINOR__ because they
# are insufficiently precise to distinguish things like
# libc-2.0.6 and libc-2.0.7.
if test -L /lib/libc.so.6; then
    libc=`ls -l /lib/libc.so.6 | awk '{print $NF}'`
    libc=/lib/$libc
fi

# Configure may fail to find lstat() since it's a static/inline
# function in <sys/stat.h>.
d_lstat=define

# malloc wrap works
case "$usemallocwrap" in
'') usemallocwrap='define' ;;
esac

# The system malloc() is about as fast and as frugal as perl's.
# Since the system malloc() has been the default since at least
# 5.001, we might as well leave it that way.  --AD  10 Jan 2002
case "$usemymalloc" in
'') usemymalloc='n' ;;
esac

# Check if we're about to use Intel's ICC compiler
case "`${cc:-cc} -V 2>&1`" in
*"Intel(R) C++ Compiler"*|*"Intel(R) C Compiler"*)
    # This is needed for Configure's prototype checks to work correctly
    ccflags="-we147 $ccflags"
    # If we're using ICC, we usually want the best performance
    case "$optimize" in
    '') optimize='-O3' ;;
    esac
    ;;
*"Sun C"*)
    optimize='-xO2'
    cccdlflags='-KPIC'
    lddlflags='-G -Bdynamic'
    ;;
esac

case "$optimize" in
# use -O2 by default ; -O3 doesn't seem to bring significant benefits with gcc
'')
    optimize='-O2'
    case "`uname -m`" in
        ppc*)
            # on ppc, it seems that gcc (at least gcc 3.3.2) isn't happy
            # with -O2 ; so downgrade to -O1.
            optimize='-O1'
        ;;
    esac
    ;;
esac

# Are we using ELF?  Thanks to Kenneth Albanowski <[email protected]>
# for this test.
cat >try.c <<'EOM'
/* Test for whether ELF binaries are produced */
#include <fcntl.h>
#include <stdlib.h>
main() {
        char buffer[4];
        int i=open("a.out",O_RDONLY);
        if(i==-1)
                exit(1); /* fail */
        if(read(i,&buffer[0],4)<4)
                exit(1); /* fail */
        if(buffer[0] != 127 || buffer[1] != 'E' ||
           buffer[2] != 'L' || buffer[3] != 'F')
                exit(1); /* fail */
        exit(0); /* succeed (yes, it's ELF) */
}
EOM
if ${cc:-gcc} try.c >/dev/null 2>&1 && $run ./a.out; then
    cat <<'EOM' >&4

You appear to have ELF support.  I'll try to use it for dynamic loading.
If dynamic loading doesn't work, read hints/linux.sh for further information.
EOM

else
    cat <<'EOM' >&4

You don't have an ELF gcc.  I will use dld if possible.  If you are
using a version of DLD earlier than 3.2.6, or don't have it at all, you
should probably upgrade. If you are forced to use 3.2.4, you should
uncomment a couple of lines in hints/linux.sh and restart Configure so
that shared libraries will be disallowed.

EOM
    lddlflags="-r $lddlflags"
    # These empty values are so that Configure doesn't put in the
    # Linux ELF values.
    ccdlflags=' '
    cccdlflags=' '
    ccflags="-DOVR_DBL_DIG=14 $ccflags"
    so='sa'
    dlext='o'
    nm_so_opt=' '
    ## If you are using DLD 3.2.4 which does not support shared libs,
    ## uncomment the next two lines:
    #ldflags="-static"
    #so='none'

        # In addition, on some systems there is a problem with perl and NDBM
        # which causes AnyDBM and NDBM_File to lock up. This is evidenced
        # in the tests as AnyDBM just freezing.  Apparently, this only
        # happens on a.out systems, so we disable NDBM for all a.out linux
        # systems.  If someone can suggest a more robust test
        #  that would be appreciated.