security/generate_mapfile.py
author Nick Alexander <nalexander@mozilla.com>
Fri, 12 Oct 2018 22:38:44 +0000
changeset 499408 91300d29898b1a1102e1b62164aeee1f56b2ee86
parent 412552 169d5dfe505f3f519d1aa14309327ad768429a90
child 499412 a06d50af52573db2ac6265ee169fc8039fbf8b04
permissions -rw-r--r--
Bug 1489443 - Set GCC_USE_GNU_LD based on linker kind. r=froydnj The desired outcome of this change is that we'll set `-Wl,--version-script` based on linker kind and not on the output of `$LINKER -v`. This is a cheap way to address a simple problem that has a complicated ideal solution. The underlying issue is that in some situations, when targeting Android, a macOS system `ld` is interrogated to determine if a cross-compiling linker "is GNU ld" and a particular linker feature is set in that situation. The macOS system `ld` doesn't pass the "is GNU ld" test, and the linker feature isn't set; that causes link failures, even though the actual linker has nothing to do with the system `ld`. The ideal solution is to test for linker capabilities dynamically. We do a lot of that in old-configure.in, and we don't do any of that in toolchain.configure. Rather than start testing in toolchain.configure, we hard-code: a cheap solution to the immediate problem. Differential Revision: https://phabricator.services.mozilla.com/D8471

#!/usr/bin/env python

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# This script processes NSS .def files according to the rules defined in
# a comment at the top of each one. The files are used to define the
# exports from NSS shared libraries, with -DEFFILE on Windows, a linker
# script on Linux, or with -exported_symbols_list on OS X.
#
# The NSS build system processes them using a series of sed replacements,
# but the Mozilla build system is already running a Python script to generate
# the file so it's simpler to just do the replacement in Python.
#
# One difference between the NSS build system and Mozilla's is that
# Mozilla's supports building on Linux for Windows using MinGW. MinGW
# expects all lines containing ;+ removed and all ;- tokens removed.

import buildconfig


def main(output, input):
    is_darwin = buildconfig.substs['OS_ARCH'] == 'Darwin'
    is_mingw = "WINNT" == buildconfig.substs['OS_ARCH'] and \
        buildconfig.substs.get('GCC_USE_GNU_LD')

    with open(input, 'rb') as f:
        for line in f:
            line = line.rstrip()
            # On everything except MinGW, remove all lines containing ';-'
            if not is_mingw and ';-' in line:
                continue
            # On OS X, remove all lines containing ';+'
            if is_darwin and ';+' in line:
                continue
            # Remove the string ' DATA '.
            line = line.replace(' DATA ', '')
            # Remove the string ';+'
            if not is_mingw:
                line = line.replace(';+', '')
            # Remove the string ';;'
            line = line.replace(';;', '')
            # If a ';' is present, remove everything after it,
            # and on OS X, remove it as well.
            i = line.find(';')
            if i != -1:
                if is_darwin or is_mingw:
                    line = line[:i]
                else:
                    line = line[:i+1]
            # On OS X, symbols get an underscore in front.
            if line and is_darwin:
                output.write('_')
            output.write(line)
            output.write('\n')