DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (d38398e5144e)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152
# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
# vim: set filetype=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/.


# Generates a test program and attempts to compile it. In case of failure, the
# resulting check will return None. If the test program succeeds, it will return
# the output of the test program.
# - `includes` are the includes (as file names) that will appear at the top of
#   the generated test program.
# - `body` is the code that will appear in the main function of the generated
#   test program. `return 0;` is appended to the function body automatically.
# - `language` is the language selection, so that the appropriate compiler is
#   used.
# - `flags` are the flags to be passed to the compiler, in addition to `-c`.
# - `check_msg` is the message to be printed to accompany compiling the test
#   program.
@template
def try_compile(includes=None, body='', language='C++', flags=None, check_msg=None,
                when=None):
    compiler = {
        'C': c_compiler,
        'C++': cxx_compiler,
    }[language]

    return compiler.try_compile(includes, body, flags, check_msg, when=when)


# Checks for the presence of the given header on the target system by compiling
# a test program including that header. The return value of the template is a
# check function returning True if the header is present, and None if it is not.
# The value of this check function is also used to set a variable (with set_define)
# corresponding to the checked header. For instance, HAVE_MALLOC_H will be set in
# defines if check_header if called with 'malloc.h' as input and malloc.h is
# present on the target.
# - `header` is the header, as a file name, to check for.
# - `language` is the language selection, so that the appropriate compiler is
#   used.
# - `flags` are the flags to be passed to the compiler, in addition to `-c`.
# - `includes` are additional includes, as file names, to appear before the
#   header checked for.
# - `when` is a depends function that if present will make performing the check
#   conditional on the value of that function.
@template
def check_header(header, language='C++', flags=None, includes=None, when=None):
    when = when or always

    if includes:
        includes = includes[:]
    else:
        includes = []
    includes.append(header)

    have_header = try_compile(includes=includes, language=language, flags=flags,
                              check_msg='for %s' % header, when=when)
    header_var = 'HAVE_%s' % (header.upper()
                                    .replace('-', '_')
                                    .replace('/', '_')
                                    .replace('.', '_'))
    set_define(header_var, have_header)
    return have_header

# A convenience wrapper for check_header for checking multiple headers.
# returns an array of the resulting checks in order corresponding to the
# provided headers.
# - `headers` are the headers to be checked.
# - `kwargs` are keyword arguments passed verbatim to check_header.
@template
def check_headers(*headers, **kwargs):
    checks = []
    for header in headers:
        checks.append(check_header(header, **kwargs))
    return checks


@dependable
def warnings_cflags():
    return []

@dependable
def warnings_cxxflags():
    return []


# Tests whether GCC or clang support the given warning flag, and if it is,
# add it to the list of warning flags for the build.
# - `warning` is the warning flag (e.g. -Wfoo)
# - `compiler` (optional) is the compiler to test against (c_compiler or
#   cxx_compiler, from toolchain.configure). When omitted, both compilers
#   are tested.
# - `when` (optional) is a @depends function or option name conditioning
#   when the warning flag is wanted.
# - `check`, when not set, skips checking whether the flag is supported and
#   adds it to the list of warning flags unconditionally. This is only meant
#   for add_gcc_warning().
@template
def check_and_add_gcc_warning(warning, compiler=None, when=None, check=True):
    if compiler:
        compilers = (compiler,)
    else:
        compilers = (c_compiler, cxx_compiler)

    when = when or always

    for c in compilers:
        assert c in (c_compiler, cxx_compiler)
        lang, warnings_flags = {
            c_compiler: ('C', warnings_cflags),
            cxx_compiler: ('C++', warnings_cxxflags),
        }[c]

        # GCC and clang will fail if given an unknown warning option like
        # -Wfoobar. But later versions won't fail if given an unknown negated
        # warning option like -Wno-foobar. So when we are checking for support
        # of a negated warning option, we actually test the positive form, but
        # add the negated form to the flags variable.
        if (warning.startswith('-Wno-') and
                not warning.startswith('-Wno-error=')):
            flags = ['-Werror', '-W' + warning[5:]]
        elif warning.startswith('-Werror='):
            flags = [warning]
        else:
            flags = ['-Werror', warning]

        @depends(c, when)
        def result(c, when):
            if when and c.type in ('clang', 'gcc'):
                return True

        if check:
            result = c.try_compile(
                flags=flags, when=result,
                check_msg='whether the %s compiler supports %s' % (lang,
                                                                   warning))

        @depends(result, warnings_flags)
        def maybe_add_flag(result, warnings_flags):
            if result:
                warnings_flags.append(warning)

# Add the given warning to the list of warning flags for the build.
# - `warning` is the warning flag (e.g. -Wfoo)
# - `compiler` (optional) is the compiler to add the flag for (c_compiler or
#   cxx_compiler, from toolchain.configure). When omitted, the warning flag
#   is added for both compilers.
# - `when` (optional) is a @depends function or option name conditioning
#   when the warning flag is wanted.
@template
def add_gcc_warning(warning, compiler=None, when=None):
    check_and_add_gcc_warning(warning, compiler, when, check=False)