<AWT Dev> RFR: [OpenJDK 2D-Dev] JDK-8215296 do not disable c99 on Solaris

Baesken, Matthias matthias.baesken at sap.com
Wed Dec 19 15:31:11 UTC 2018 

>
> Sounds like a simpler change, at least for now. Does it pass jdk-submit?
>

Hello Magnus ,   pushed it to  jdk/submit  , however I do not expect  much info from it because David  told me Solaris is not tested there 
 (and the other platforms are not affected by my path).

However David tested it Oracle-internally   with success .

Can I add you and David as reviewers ?


Best regards, Matthias



> -----Original Message-----
> From: Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com>
> Sent: Montag, 17. Dezember 2018 16:11
> To: Baesken, Matthias <matthias.baesken at sap.com>
> Cc: 2d-dev at openjdk.java.net; erik.joelsson at oracle.com; build-
> dev at openjdk.java.net; awt-dev at openjdk.java.net
> Subject: Re: RFR: [OpenJDK 2D-Dev] JDK-8215296 do not disable c99 on
> Solaris
> 
> Sounds like a simpler change, at least for now. Does it pass jdk-submit? Do
> you intend to push to 12 or 13?
> 
> Looks good to me, as long as it doesn't break anything.
> 
> /Magnus
> 
> > 17 dec. 2018 kl. 14:12 skrev Baesken, Matthias
> <matthias.baesken at sap.com>:
> >
> >
> > Hello,  please review
> >
> > http://cr.openjdk.java.net/~mbaesken/webrevs/8215296.0/
> >
> > in my change just -xc99=%none  is removed, so we do not forbid c99
> coding.
> >
> > The -Xa compile flag is kept,  no special additional settings are needed to
> compile png/awt .
> >
> >
> > Thanks, Matthias
> >
> >
> >> ----------------------------------------------------------------------
> >>
> >> Message: 1
> >> Date: Fri, 14 Dec 2018 15:39:26 +0100
> >> From: Magnus Ihse Bursie <magnus.ihse.bursie at oracle.com>
> >> To: Erik Joelsson <erik.joelsson at oracle.com>, build-dev
> >>    <build-dev at openjdk.java.net>, "awt-dev at openjdk.java.net"
> >>    <awt-dev at openjdk.java.net>, 2d-dev <2d-dev at openjdk.java.net>
> >> Subject: Re: [OpenJDK 2D-Dev] RFR: JDK-8215296 do not disable c99 on
> >>    Solaris
> >> Message-ID: <5874d10e-db2d-8681-a54b-a1eeb6e45994 at oracle.com>
> >> Content-Type: text/plain; charset=utf-8; format=flowed
> >>
> >>
> >>
> >>> On 2018-12-14 12:49, Magnus Ihse Bursie wrote:
> >>>
> >>> 13 dec. 2018 kl. 19:07 skrev Erik Joelsson <erik.joelsson at oracle.com
> >>> <mailto:erik.joelsson at oracle.com>>:
> >>>
> >>>>
> >>>>> On 2018-12-13 02:11, Magnus Ihse Bursie wrote:
> >>>>>
> >>>>>> -D_XPG6
> >>>>>>
> >>>>>> ??
> >>>>> To be honest, I'm not completely sure about this. Without this
> >>>>> define, the build failed with the following error message:
> >>>>> Compiler or options invalid for pre-UNIX 03 X/Open applications and
> >>>>> pre-2001 POSIX applications
> >>>>>
> >>>>> This was triggered by the following section in
> >>>>> /usr/include/sys/feature_tests.h:
> >>>>> /*
> >>>>> * It is invalid to compile an XPG3, XPG4, XPG4v2, or XPG5 application
> >>>>> * using c99.  The same is true for POSIX.1-1990, POSIX.2-1992,
> >>>>> POSIX.1b,
> >>>>> * and POSIX.1c applications. Likewise, it is invalid to compile an
> >>>>> XPG6
> >>>>> * or a POSIX.1-2001 application with anything other than a c99 or
> >>>>> later
> >>>>> * compiler.  Therefore, we force an error in both cases.
> >>>>> */
> >>>>> #if defined(_STDC_C99) && (defined(__XOPEN_OR_POSIX) &&
> >>>>> !defined(_XPG6))
> >>>>> #error "Compiler or options invalid for pre-UNIX 03 X/Open
> >>>>> applications \
> >>>>>        and pre-2001 POSIX applications"
> >>>>> #elif !defined(_STDC_C99) && \
> >>>>>        (defined(__XOPEN_OR_POSIX) && defined(_XPG6))
> >>>>> #error "Compiler or options invalid; UNIX 03 and POSIX.1-2001
> >>>>> applications \
> >>>>>        require the use of c99"
> >>>>> #endif
> >>>>>
> >>>>> The solution, as also hinted to by searching for other resolutions
> >>>>> to this error online, was to provide the _XPG6 system define. But
> >>>>> exactly how we end up in feature_tests.h with __XOPEN_OR_POSIX
> set,
> >>>>> without _XPG6 set, and only when compiling this library and not
> >>>>> others, I don't know. I also don't understand what the XPG standard
> >>>>> refers to, nor what versions 2-5 means or what version 6 has that
> >>>>> differs from them.
> >>>>>
> >>>>> By setting this flag, I am telling solaris include headers that we
> >>>>> want to compile using the XPG standard version 6, instead of an
> >>>>> older one. It solves the problem. I am happy enough with this. Are
> you?
> >>>> It looks like this comes from libpng. It has this in
> >>>> src/java.desktop//share/native/libsplashscreen/libpng/pngpriv.h:
> >>>>
> >>>> /* Feature Test Macros.  The following are defined here to ensure
> >>>> that correctly
> >>>> * implemented libraries reveal the APIs libpng needs to build and
> >>>> hide those
> >>>> * that are not needed and potentially damaging to the compilation.
> >>>> *
> >>>> * Feature Test Macros must be defined before any system header is
> >>>> included (see
> >>>> * POSIX 1003.1 2.8.2 "POSIX Symbols."
> >>>> *
> >>>> * These macros only have an effect if the operating system supports
> >>>> either
> >>>> * POSIX 1003.1 or C99, or both.  On other operating systems
> >>>> (particularly
> >>>> * Windows/Visual Studio) there is no effect; the OS specific tests
> >>>> below are
> >>>> * still required (as of 2011-05-02.)
> >>>> */
> >>>> #ifndef _POSIX_SOURCE
> >>>> # define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
> >>>> #endif
> >>>>
> >>>> This in turn triggers _XOPEN_OR_POSIX to be defined in
> >>>> /usr/include/sys/feature_tests.h and so triggers the error.
> >>>>
> >>>> What I'm not clear about is if libpng is trying to declare that it
> >>>> should not be compiled with any newer standards, and so by doing
> >>>> that, we risk introducing problems. Reading in the system header, it
> >>>> seems the _XPG6 macro is internal and should not be used by the
> >>>> application. It's derived from _XOPEN_SOURCE=600 or
> >>>> _POSIX_C_SOURCE=200112L which is what applications should use.
> >>>
> >>> Interesting. We should probably define one, or both of these. Perhaps
> >>> globally for all native files and compilers. It might have been the
> >>> case that the solstudio compiler set _POSIX_C_SOURCE for us before,
> >>> prior to setting -std=c99. The following stack overflow article claims
> >>> that this is at least the behavior of gcc/clang:
> >>>
> >>> https://stackoverflow.com/questions/21867897/c89-and-posix-at-the-
> >> same-time
> >>>
> >>>
> >>> So we might have had an implicit _POSIX_C_SOURCE that we now miss.
> >>> That would explain why this starts to fail. I'll see if I can confirm
> >>> this the next time I log into a Solaris computer.
> >> Of course it was not as simple. Setting:
> >>   ifeq ($(OPENJDK_TARGET_OS), solaris)
> >>     LIBSPLASHSCREEN_CFLAGS += -D_POSIX_C_SOURCE=200112L -
> >> D_XOPEN_SOURCE=600
> >>   endif
> >>
> >> instead made us fail with:
> >> open/src/java.desktop/unix/native/libsplashscreen/splashscreen_sys.c",
> >> line 143: error: incomplete struct/union/enum timezone: tz
> >>
> >> I don't have more time to dig into this now. Overall, changes such as
> >> these make it all feel a bit scary; I recommend that any change to this
> >> be made in JDK 13 and not 12.
> >>
> >> /Magnus
> >>>
> >>> Otoh, the same article claims, and it sounds reasonable, that we
> >>> should set these variables ourself, to be well behaved and to minimize
> >>> surprises. And I think this applies to all unix platforms, regardless
> >>> of compiler being used. I'll see if I can kick off a test job with
> >>> this to see how/if it influences other platforms. But it sounds like
> >>> something we should do; the level of posix conformance should be
> >>> controlled by us, not left to chance. We also need to verify, of
> >>> course, that all platforms we want to support is capable of
> >>> supporting  _POSIX_C_SOURCE=200112L. I doubt there's a problem
> >> though.
> >>> Possibly on AIX...
> >>>
> >>> /Magnus
> >>>
> >>>>
> >>>> So the the question is, is it ok to override the requirements of
> >>>> libpng or should it receive special treatment? If we are fine with
> >>>> overriding, then we should use one of the public APIs instead.
> >>>>
> >>>> /Erik
> >>>>
> >>>>> /Magnus
> >>>>>
> >>>>>>
> >>>>>> Thanks,
> >>>>>> David
> >>>>>>
> >>>>>>> On 13/12/2018 7:02 am, Magnus Ihse Bursie wrote:
> >>>>>>>
> >>>>>>>
> >>>>>>>> On 2018-12-12 20:08, Magnus Ihse Bursie wrote:
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>> On 2018-12-12 19:12, Magnus Ihse Bursie wrote:
> >>>>>>>>> From the bug report:
> >>>>>>>>> "Currently  we disable C99 in the Solaris build by setting
> >>>>>>>>> -xc99=%none%.
> >>>>>>>>> This differs from a lot of other build environments like
> >>>>>>>>> gcc/Linux or VS2013/2017 on Windows where C99 features work.
> >>>>>>>>> We should remove this difference on Solaris and remove or
> >>>>>>>>> replace the setting.
> >>>>>>>>>
> >>>>>>>>> Kim Barrett mentioned :
> >>>>>>>>> "I merely mentioned the C++14 work as evidence that removing
> >>>>>>>>> -xc99=%none% didn?t appear harmful."
> >>>>>>>>> However it will take more time until  the C++14 change is in."
> >>>>>>>>>
> >>>>>>>>> I am currently running a test build on our CI build system to
> >>>>>>>>> confirm that this does not break the Solaris build (but I'd be
> >>>>>>>>> highly surprised if it did). I will not push this until the
> >>>>>>>>> builds are cleared.
> >>>>>>>> Of course it was not that simple... :-( Two AWT libraries (at
> >>>>>>>> least) failed to build. I'm currently investigating if there's a
> >>>>>>>> simple fix to that.
> >>>>>>> New attempt, that fixes the two AWT libraries:
> >>>>>>> WebRev:
> >>>>>>> http://cr.openjdk.java.net/~ihse/JDK-8215296-build-solstudio-
> with-
> >> c99/webrev.01
> >>>>>>> <http://cr.openjdk.java.net/%7Eihse/JDK-8215296-build-solstudio-
> >> with-c99/webrev.01>
> >>>>>>>
> >>>>>>>
> >>>>>>> Now this passes the CI build test.
> >>>>>>>
> >>>>>>> /Magnus
> >>>>>>>>
> >>>>>>>> /Magnus
> >>>>>>>>>
> >>>>>>>>> /Magnus
> >>>>>>>>>
> >>>>>>>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8215296
> >>>>>>>>> Patch inline:
> >>>>>>>>> diff --git a/make/autoconf/flags-cflags.m4
> >>>>>>>>> b/make/autoconf/flags-cflags.m4
> >>>>>>>>> --- a/make/autoconf/flags-cflags.m4
> >>>>>>>>> +++ b/make/autoconf/flags-cflags.m4
> >>>>>>>>> @@ -559,7 +559,7 @@
> >>>>>>>>> TOOLCHAIN_CFLAGS="-errshort=tags"
> >>>>>>>>>
> >>>>>>>>> TOOLCHAIN_CFLAGS_JDK="-mt $TOOLCHAIN_FLAGS"
> >>>>>>>>> - TOOLCHAIN_CFLAGS_JDK_CONLY="-xc99=%none -xCC -Xa -
> W0,-
> >> noglobal
> >>>>>>>>> $TOOLCHAIN_CFLAGS" # C only
> >>>>>>>>> + TOOLCHAIN_CFLAGS_JDK_CONLY="-std=c99 -xCC -W0,-
> noglobal
> >>>>>>>>> $TOOLCHAIN_CFLAGS" # C only
> >>>>>>>>> TOOLCHAIN_CFLAGS_JDK_CXXONLY="-features=no%except -
> >> norunpath
> >>>>>>>>> -xnolib" # CXX only
> >>>>>>>>> TOOLCHAIN_CFLAGS_JVM="-template=no%extdef -
> >> features=no%split_init \
> >>>>>>>>>         -library=stlport4 -mt -features=no%except
> >>>>>>>>> $TOOLCHAIN_FLAGS"
> >

More information about the awt-dev mailing list