Re: [ANN] Lua 5.3.0 (rc3) now available

[Edward Berner <erb@...>]

On 1/2/2015 5:36 AM, Luiz Henrique de Figueiredo wrote:
> Lua 5.3.0 (rc3) is now available for testing at
> 	http://www.lua.org/work/lua-5.3.0-rc3.tar.gz
>
> MD5	5dd17d29fbb70139d315e2cea751a128  -
> SHA1	83e26c3c21abe7c309c5e9df08b6a7a7db85ef2a  -
>
> This is a release candidate for the final release of Lua 5.3.0.
>
> [...]
> All feedback welcome. Thanks.
> --lhf

Compiles nicely on Solaris.  Thanks!

It builds without warnings with gcc 4.8.1 and Solaris Studio 12.3. The 
gcc included with Solaris 10 (gcc 3.4.3) complains about a visibility 
attribute not being supported, and about luaD_throw in ldo.c being a 
noreturn function that does return (neither of those warnings is new to 
RC3).  (The visibility attribute warnings can be silenced using the 
existing configurable parameter LUAI_FUNC in luaconf.h.)

To get support for hexadecimal floating point constants when using gcc 
on Solaris it seems to be necessary to link to values-xpg6.o. The 
Solaris Studio compilers include it automatically in c99 mode, but gcc 
doesn't (yet?).  If I understand correctly, explicitly linking 
values-xpg6.o in a library can cause surprising behavior if the 
application using the library didn't expect to suddenly get c99 
behaviors.  So Lua itself probably shouldn't link to values-xpg6.o, but 
if there is a section in the readme or other documentation for platform 
specific notes, maybe it could be mentioned there.

For more information about values-xpg6.o, there is a gcc bug:

    -std=c99 does not enable c99 mode in Solaris C library
    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=40411

A couple mailing list discussions:

    -xc99=all and libraries on Solaris 10
    http://lists.gnu.org/archive/html/autoconf/2010-02/msg00013.html

    Re: -xc99=all and libraries on Solaris 10
    http://lists.gnu.org/archive/html/autoconf/2010-12/msg00059.html

And the Open Solaris source code:

http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/common/common/values-xpg6.c
http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libc/inc/xpg6.h

So, anyway... I built Lua, linked with values-xpg6.o, and ran the test 
suite with "_U=true".  All of the tests except two completed 
successfully.  The two failing tests were lines 285 and 295 of 
files.lua, which try to read from a write only file; I traced the 
failure down to Solaris not setting ferror():

    #include <stdio.h>
    #include <errno.h>

    int main (int argc, char *argv[]) {
            int c, e;
            FILE *f;

            f = fopen ("/tmp/z", "w");
            if (f == NULL) {
                    perror ("fopen");
                    return 1;
            }
            clearerr (f);
            errno = 0;
            c = getc (f);
            e = errno;
            printf ("c = %d\n", c);
            printf ("errno = %d\n", e);
            printf ("ferror(f) = %d\n", ferror(f));
            printf ("feof(f) == %d\n", feof(f));
            fclose (f);
            return 0;
    }

On Solaris:

    c = -1
    errno = 9
    ferror(f) = 0
    feof(f) == 0

On Linux and OpenBSD:

    c = -1
    errno = 9
    ferror(f) = 1
    feof(f) == 0

Oh well, an operating system anomaly but not an issue with Lua itself.

In summary: looks good on Solaris.  Thanks.

--
Edward Berner