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[autobuild.buildroot.net] Build results for 2016-12-02

Message ID 20161203233249.08ff4c7b@gmx.net
State Not Applicable
Headers show

Commit Message

Peter Seiderer Dec. 3, 2016, 10:32 p.m. UTC 
Hello,

On Sat,  3 Dec 2016 08:30:24 +0100 (CET), Thomas Petazzoni <thomas.petazzoni@free-electrons.com> wrote:

> Hello,
> 
> Build statistics for 2016-12-02
> ================================

> microblazeel |              gstreamer1-1.10.2 | NOK | http://autobuild.buildroot.net/results/c1cd60d3f44f2938e5f42453d034ea070898f837
>       xtensa |              gstreamer1-1.10.2 | NOK | http://autobuild.buildroot.net/results/c3a6662f0acfda179a58cdad9165f36826229826

  CC       libgstreamer_1.0_la-gstbus.lo
In file included from gst_private.h:42:0,
                 from gstbufferpool.c:66:
../gst/gstconfig.h:112:4: error: #error "Could not detect architecture; don't know whether it supports unaligned access! Please file a bug."
 #  error "Could not detect architecture; don't know whether it supports unaligned access! Please file a bug."


This error message was introduces between gstreamer-1.8 and 1.10 with
commit 'gstconfig.h: Detect unaligned access support at compile-time' ([1]):

unaligned acess yes/no?

Regards,
Peter

[1] https://cgit.freedesktop.org/gstreamer/gstreamer/commit/?h=1.10&id=6ef601367e0f5adb7a8b02cec94dec04fccf701a

Comments

Thomas Petazzoni Dec. 4, 2016, 2:11 p.m. UTC | #1 
Hello,

Adding in Cc: Waldemar for Microblaze, and Max for Xtensa.

On Sat, 3 Dec 2016 23:32:49 +0100, Peter Seiderer wrote:

> +#if defined(__alpha__) || defined(__arm__) || defined(__aarch64__) || defined(__bfin) || defined(__hppa__) || defined(__mips__) || defined(__sh__) || defined(__sparc__) || defined(__sparc) || defined(__ia64__) || defined(_M_ALPHA) || defined(_M_ARM) || defined(_M_IA64)
> +#  define GST_HAVE_UNALIGNED_ACCESS 0
> +#elif defined(__i386__) || defined(__i386) || defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__ppc__) || defined(__ppc64__) || defined(__m68k__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
> +#  define GST_HAVE_UNALIGNED_ACCESS 1
> +#else
> +#  error "Could not detect architecture; don't know whether it supports unaligned access! Please file a bug."
> +#endif
> 
> Time to add defines for microblazeel and xtensa, any hint which defines and at
> unaligned acess yes/no?

Do you think there would be a problem to simply assume by default that
the architecture doesn't support unaligned accesses? I mean, if a new
architecture by chance supports unaligned accesses, but we tell
GStreamer that we don't support such unaligned accesses, what can go
wrong? Possibly the code is slightly less efficient, but there should
be no runtime issue.

So what about instead doing:

#if defined(__i386__) || defined(__i386) || defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__ppc__) || defined(__ppc64__) || defined(__m68k__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
#  define GST_HAVE_UNALIGNED_ACCESS 1
#else
#  define GST_HAVE_UNALIGNED_ACCESS 0
#endif

and be done with it?

Best regards,

Thomas
Max Filippov Dec. 5, 2016, 3:29 a.m. UTC | #2 
On Sun, Dec 4, 2016 at 6:11 AM, Thomas Petazzoni
<thomas.petazzoni@free-electrons.com> wrote:
> Hello,
>
> Adding in Cc: Waldemar for Microblaze, and Max for Xtensa.
>
> On Sat, 3 Dec 2016 23:32:49 +0100, Peter Seiderer wrote:
>
>> +#if defined(__alpha__) || defined(__arm__) || defined(__aarch64__) || defined(__bfin) || defined(__hppa__) || defined(__mips__) || defined(__sh__) || defined(__sparc__) || defined(__sparc) || defined(__ia64__) || defined(_M_ALPHA) || defined(_M_ARM) || defined(_M_IA64)
>> +#  define GST_HAVE_UNALIGNED_ACCESS 0
>> +#elif defined(__i386__) || defined(__i386) || defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__ppc__) || defined(__ppc64__) || defined(__m68k__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
>> +#  define GST_HAVE_UNALIGNED_ACCESS 1
>> +#else
>> +#  error "Could not detect architecture; don't know whether it supports unaligned access! Please file a bug."
>> +#endif
>>
>> Time to add defines for microblazeel and xtensa, any hint which defines and at
>> unaligned acess yes/no?

For xtensa it would be __xtensa__, but there's currently no easy way to tell
if the core supports unaligned access or not, so should default to "no".

> Do you think there would be a problem to simply assume by default that
> the architecture doesn't support unaligned accesses? I mean, if a new
> architecture by chance supports unaligned accesses, but we tell
> GStreamer that we don't support such unaligned accesses, what can go
> wrong? Possibly the code is slightly less efficient, but there should
> be no runtime issue.
>
> So what about instead doing:
>
> #if defined(__i386__) || defined(__i386) || defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__ppc__) || defined(__ppc64__) || defined(__m68k__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
> #  define GST_HAVE_UNALIGNED_ACCESS 1
> #else
> #  define GST_HAVE_UNALIGNED_ACCESS 0
> #endif
>
> and be done with it?

+1 to this.
diff mbox

Patch

diff --git a/gst/gstconfig.h.in b/gst/gstconfig.h.in
index 8654627..0ec1509 100644
--- a/gst/gstconfig.h.in
+++ b/gst/gstconfig.h.in
@@ -95,8 +95,22 @@ 
 /* Configures the use of external plugins */
 @GST_DISABLE_PLUGIN_DEFINE@
 
-/* whether or not the CPU supports unaligned access */
-@GST_HAVE_UNALIGNED_ACCESS_DEFINE@
+/* Whether or not the CPU supports unaligned access
+ * The macros used are defined consistently by GCC, Clang, MSVC, Sun, and ICC
+ *
+ * References:
+ * https://sourceforge.net/p/predef/wiki/Architectures/
+ * https://msdn.microsoft.com/en-us/library/b0084kay.aspx
+ * http://docs.oracle.com/cd/E19205-01/820-4155/c++_faq.html#Vers6
+ * https://software.intel.com/en-us/node/583402
+ */
+#if defined(__alpha__) || defined(__arm__) || defined(__aarch64__) || defined(__bfin) || defined(__hppa__) || defined(__mips__) || defined(__sh__) || defined(__sparc__) || defined(__sparc) || defined(__ia64__) || defined(_M_ALPHA) || defined(_M_ARM) || defined(_M_IA64)
+#  define GST_HAVE_UNALIGNED_ACCESS 0
+#elif defined(__i386__) || defined(__i386) || defined(__amd64__) || defined(__amd64) || defined(__x86_64__) || defined(__ppc__) || defined(__ppc64__) || defined(__m68k__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
+#  define GST_HAVE_UNALIGNED_ACCESS 1
+#else
+#  error "Could not detect architecture; don't know whether it supports unaligned access! Please file a bug."
+#endif


Time to add defines for microblazeel and xtensa, any hint which defines and at