This goes back 5 or more years ago so my recollection might be off but I had issues with GCC 4.5.2 using -mfloat-abi=hard. NXP recommends -mfloat-abi=softfp. I can't find the article or forum now but I think it had to do with the fact that the LPC3250 VFP didn't support all the required instructions for -mfloat-abi=hard (something about needing a Undefined Instruction exception handler to process unsupported VFP instructions). Using -mfloat-abi=softfp eliminates the need for the Undefined Instruction exception handler to handle unsupported VFP instructions.
Kevin Kirspel Electrical Engineer - Sr. Staff Opti Medical 235 Hembree Park Drive Roswell GA 30076 Tel: (770)-510-4444 ext. 81642 Direct: (770)-688-1642 Fax: (770)-510-4445 -----Original Message----- From: Sebastian Huber [mailto:sebastian.hu...@embedded-brains.de] Sent: Friday, August 19, 2016 1:22 AM To: Kirspel, Kevin <kevin-kirs...@idexx.com>; devel@rtems.org Subject: Re: [PATCH 1/2] RTEMS Source Builder changes for lpc32xx VFP support On 19/08/16 02:11, Kirspel, Kevin wrote: > > diff --git > a/source-builder/patches/gcc-6.1.1-arm-eabi-multilib-20160816.diff > b/source-builder/patches/gcc-6.1.1-arm-eabi-multilib-20160816.diff > > index e69de29..d2f0bfd 100755 > > --- a/source-builder/patches/gcc-6.1.1-arm-eabi-multilib-20160816.diff > > +++ b/source-builder/patches/gcc-6.1.1-arm-eabi-multilib-20160816.diff > > @@ -0,0 +1,18 @@ > > +diff -ruN gcc-6-20160609.orig/gcc/config/arm/t-rtems > gcc-6-20160609/gcc/config/arm/t-rtems > > +--- gcc-6-20160609.orig/gcc/config/arm/t-rtems 2016-01-15 > 03:29:12.000000000 -0800 > > ++++ gcc-6-20160609/gcc/config/arm/t-rtems 2016-08-16 > 11:42:02.727219302 -0700 > > +@@ -1,7 +1,7 @@ > > + # Custom RTEMS multilibs for ARM > > + > > +-MULTILIB_OPTIONS = mbig-endian mthumb > march=armv6-m/march=armv7-a/march=armv7-r/march=armv7-m/mcpu=cortex-m7 > mfpu=neon/mfpu=vfpv3-d16/mfpu=fpv4-sp-d16/mfpu=fpv5-d16 mfloat-abi=hard > > +-MULTILIB_DIRNAMES = eb thumb armv6-m armv7-a armv7-r armv7-m > cortex-m7 neon vfpv3-d16 fpv4-sp-d16 fpv5-d16 hard > > ++MULTILIB_OPTIONS = mbig-endian mthumb > march=armv6-m/march=armv7-a/march=armv7-r/march=armv7-m/mcpu=cortex-m7 > mfpu=neon/mfpu=vfp/mfpu=vfpv3-d16/mfpu=fpv4-sp-d16/mfpu=fpv5-d16 > mfloat-abi=hard/mfloat-abi=softfp > > ++MULTILIB_DIRNAMES = eb thumb armv6-m armv7-a armv7-r armv7-m > cortex-m7 neon vfp vfpv3-d16 fpv4-sp-d16 fpv5-d16 hard softfp > > + > > + # Enumeration of multilibs > > + > > +@@ -19,3 +19,4 @@ > > + MULTILIB_REQUIRED += mthumb/mcpu=cortex-m7/mfpu=fpv5-d16/mfloat-abi=hard > > + MULTILIB_REQUIRED += mthumb/march=armv7-m > > + MULTILIB_REQUIRED += mthumb > > ++MULTILIB_REQUIRED += mfpu=vfp/mfloat-abi=softfp > Why do you want to use the softfp ABI? -- Sebastian Huber, embedded brains GmbH Address : Dornierstr. 4, D-82178 Puchheim, Germany Phone : +49 89 189 47 41-16 Fax : +49 89 189 47 41-09 E-Mail : sebastian.hu...@embedded-brains.de PGP : Public key available on request. Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG. _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel