gcc/libtool-ldflags

#! /bin/sh

# Script to translate LDFLAGS into a form suitable for use with libtool.

# Copyright (C) 2005-2014 Free Software Foundation, Inc.
#
# This file is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 
# MA 02110-1301, USA. 

# Contributed by CodeSourcery, LLC.

# This script is designed to be used from a Makefile that uses libtool
# to build libraries as follows: 
#
#   LTLDFLAGS = $(shell libtool-ldflags $(LDFLAGS))
#
# Then, use (LTLDFLAGS) in place of $(LDFLAGS) in your link line.

# The output of the script.  This string is built up as we process the
# arguments.
result=
prev_arg=

for arg
do
    case $arg in
	-f*|--*|-static-lib*|-shared-lib*|-B*)
	    # Libtool does not ascribe any special meaning options
	    # that begin with -f or with a double-dash.  So, it will
	    # think these options are linker options, and prefix them
	    # with "-Wl,".  Then, the compiler driver will ignore the
	    # options.  So, we prefix these options with -Xcompiler to
	    # make clear to libtool that they are in fact compiler
	    # options.  Similarly for e.g. -static-libstdc++, or
	    # -B/some/path.
	    case $prev_arg in
		-Xpreprocessor|-Xcompiler|-Xlinker)
		    # This option is already prefixed; don't prefix it again.
		    ;;
		*)
		    result="$result -Xcompiler"
		    ;;
	    esac
	    ;;
	*)
	    # We do not want to add -Xcompiler to other options because
	    # that would prevent libtool itself from recognizing them.
	    ;;
    esac
    prev_arg=$arg

    # If $(LDFLAGS) is (say):
    #   a "b'c d" e
    # then the user expects that:
    #   $(LD) $(LDFLAGS)
    # will pass three arguments to $(LD):
    #   1) a
    #   2) b'c d
    #   3) e
    # We must ensure, therefore, that the arguments are appropriately
    # quoted so that using:
    #   libtool --mode=link ... $(LTLDFLAGS)
    # will result in the same number of arguments being passed to
    # libtool.   In other words, when this script was invoked, the shell 
    # removed one level of quoting, present in $(LDFLAGS); we have to put 
    # it back.

    # Quote any embedded single quotes.
    case $arg in
	*"'"*)
	    # The following command creates the script:
	    #   1s,^X,,;s|'|'"'"'|g
	    # which removes a leading X, and then quotes and embedded single
	    # quotes.
	    sed_script="1s,^X,,;s|'|'\"'\"'|g"
	    # Add a leading "X" so that if $arg starts with a dash,
	    # the echo command will not try to interpret the argument
	    # as a command-line option.
	    arg="X$arg"
	    # Generate the quoted string.
	    quoted_arg=`echo "$arg" | sed -e "$sed_script"`
	    ;;
	*)
	    quoted_arg=$arg
	    ;;
    esac
    # Surround the entire argument with single quotes.
    quoted_arg="'"$quoted_arg"'" 

    # Add it to the string.
    result="$result $quoted_arg"
done

# Output the string we have built up.
echo "$result"