[Mesa-dev] [PATCH 09/15] scons: Prefer winflexbison, and use --wincompat when available.

[Brian Paul]

On 03/20/2015 07:59 AM, Jose Fonseca wrote:
> This avoids MSVC the warning
>
>    warning C4013: 'isatty' undefined; assuming extern returning int
>
> with certain versions of flex.
> ---
>   scons/gallium.py | 39 ++++++++++++++++++++++++++++++++-------
>   1 file changed, 32 insertions(+), 7 deletions(-)
>
> diff --git a/scons/gallium.py b/scons/gallium.py
> index 9924f1e..9fe2dbd 100755
> --- a/scons/gallium.py
> +++ b/scons/gallium.py
> @@ -35,7 +35,7 @@ import os
>   import os.path
>   import re
>   import subprocess
> -import platform as _platform
> +import platform as host_platform
>   import sys
>   import tempfile
>
> @@ -147,6 +147,15 @@ def check_cc(env, cc, expr, cpp_opt = '-E'):
>       return result
>
>
> +def check_prog(env, prog):

Maybe put a """comment""" here to explain what this function does.


> +    sys.stdout.write('Checking for %s ... ' % prog)
> +
> +    result = env.Detect(prog)
> +
> +    sys.stdout.write(' %s\n' % ['no', 'yes'][int(bool(result))])
> +    return result
> +
> +
>   def generate(env):
>       """Common environment generation code"""
>
> @@ -186,7 +195,7 @@ def generate(env):
>       env['gcc'] = 0
>       env['clang'] = 0
>       env['msvc'] = 0
> -    if _platform.system() == 'Windows':
> +    if host_platform.system() == 'Windows':
>           env['msvc'] = check_cc(env, 'MSVC', 'defined(_MSC_VER)', '/E')
>       if not env['msvc']:
>           env['gcc'] = check_cc(env, 'GCC', 'defined(__GNUC__) && !defined(__clang__)')
> @@ -210,10 +219,10 @@ def generate(env):
>
>       # Determine whether we are cross compiling; in particular, whether we need
>       # to compile code generators with a different compiler as the target code.
> -    host_platform = _platform.system().lower()
> -    if host_platform.startswith('cygwin'):
> -        host_platform = 'cygwin'
> -    host_machine = os.environ.get('PROCESSOR_ARCHITEW6432', os.environ.get('PROCESSOR_ARCHITECTURE', _platform.machine()))
> +    hosthost_platform = host_platform.system().lower()
> +    if hosthost_platform.startswith('cygwin'):
> +        hosthost_platform = 'cygwin'
> +    host_machine = os.environ.get('PROCESSOR_ARCHITEW6432', os.environ.get('PROCESSOR_ARCHITECTURE', host_platform.machine()))
>       host_machine = {
>           'x86': 'x86',
>           'i386': 'x86',
> @@ -224,7 +233,7 @@ def generate(env):
>           'AMD64': 'x86_64',
>           'x86_64': 'x86_64',
>       }.get(host_machine, 'generic')
> -    env['crosscompile'] = platform != host_platform
> +    env['crosscompile'] = platform != hosthost_platform
>       if machine == 'x86_64' and host_machine != 'x86_64':
>           env['crosscompile'] = True
>       env['hostonly'] = False
> @@ -630,7 +639,23 @@ def generate(env):
>               # disable all MSVC extensions.
>               '-DYY_USE_CONST=',
>           ])
> +    if host_platform.system() == 'Windows':
> +        # Prefer winflexbison binaries -- http://winflexbison.sourceforge.net/
> +        # --, as not only they are easier to install (no additional
> +        # dependencies), but also better Windows support.
> +        if check_prog(env, 'win_flex'):
> +            env["LEX"] = 'win_flex'
> +            env.Append(LEXFLAGS = [
> +                # windows compatibility (uses <io.h> instead of <unistd.h> and
> +                # _isatty, _fileno functions)
> +                '--wincompat'
> +            ])
> +
>       env.Tool('yacc')
> +    if host_platform.system() == 'Windows':
> +        if check_prog(env, 'win_bison'):
> +            env["YACC"] = 'win_bison'
> +
>       if env['llvm']:
>           env.Tool('llvm')
>
>

I wasn't aware of winflexbison.  We should probably put a link to it on 
the http://www.mesa3d.org/install.html#prereq-general page.

-Brian