-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 20-02-11 17:05, Jonathan Wilson wrote: > On Sun, 2011-02-20 at 09:14 +0100, Koen Kooi wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> On 19-02-11 20:28, Jonathan Wilson wrote: >>> Bitbake bombs out with:- >>> >>> ERROR: Build >>> of >>> /home/wilsonjonathan/oebeagle/angstrom-setup-scripts/sources/openembedded/recipes/gnome/pyorbit_2.24.0.bb >>> do_configure failed >>> ERROR: Task 8977 >>> (/home/wilsonjonathan/oebeagle/angstrom-setup-scripts/sources/openembedded/recipes/gnome/pyorbit_2.24.0.bb, >>> do_configure) failed with exit code 1 >>> >>> Changes manually made to files before compilation. >>> >>> local.conf >>> BB_NUMBER_THREADS = "2" >>> >>> DISTRO = "angstrom-2010.x" >>> MACHINE ?= "beagleboard" >>> >>> # Set TMPDIR instead of defaulting it to /tmp >>> TMPDIR = >>> >>> "/home/wilsonjonathan/oebeagle/angstrom-setup-scripts/build/tmp-angstrom_2010.x" >>> >>> tune-cortexa8.inc >>> ARM_FP_MODE ?= "hardfp" >> >> Why are you changing that there? You are supposed to set that in local.conf > > Total lack of understanding of the language used in .bb files. Re: "?=" > which I'm guessing does mean if variable is not set then set it. > > I'm not a pc programmer, AS/400's application programmer by trade, but > rather a hobbyist playing around with arm linux since getting some > rather cool NAT's to store my photo library. > >> >>> To produce hard float, -funsafe... was added due to a note on the TI >>> website. >> >> It works well without that flag, which website told you to add it? > > As per the gcc website : > http://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html > > If the selected floating-point hardware includes the NEON > extension (e.g. -mfpu=`neon'), note that floating-point > operations will not be used by GCC's auto-vectorization pass > unless -funsafe-math-optimizations is also specified. This is > because NEON hardware does not fully implement the IEEE 754 > standard for floating-point arithmetic (in particular denormal > values are treated as zero), so the use of NEON instructions may > lead to a loss of precision. > > Which as I read it means that it wont vectorise causing a possible > performance hit, although its debatable how much of difference in > performance there would be in practise.
The vectorizer in gcc sucks, so in the rare cases when it vectorizes, it generally is a lot slower than plain old vfp. The default sets in angstrom are basically as fast as you can safely get :) regards, Koen -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (Darwin) iD8DBQFNYUCJMkyGM64RGpERAkqXAJ4x5a0zkiiesfXMAYalM5uXeTX8RwCeNVJS BIwEqDc0njaSITdlI/9IhXk= =jvOi -----END PGP SIGNATURE----- _______________________________________________ Angstrom-distro-devel mailing list [email protected] http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/angstrom-distro-devel
