ARM Toolchain will be changed in MeeGo release 1.2. This page describes the change and the effects of the change.
This change effects to ARM cross compiler part of MeeGo toolchain.
The toolchain in current MeeGo 1.1 supports ARM architecture only partially what comes to Floating Point Unit (FPU) support.
gcc compiler provides three options to support floating points in option -mfloat-abi :
Full utilization of the FPU gives performance improvement to applications using plenty of floating point operations - like games, location based services and graphics.
In order to take -mfloat-abi=hard option into use in MeeGo 1.2 the toolchain is needed to be updated to gcc-4.5.1 based.
The change proposal (SDK/Toolchains/ToolchainChangeProposal) was approved in MeeGo TSG on December 1, 2010.
In MeeGo Release 1.2 and onwards the following is about to change:
* RPM architecture name: "armv7hl" * ARMv7 architecture (-march=armv7-a) * VFPv3-D16 is in use (-mfpu=vfpv3-d16) * Thumb2 instruction set not used (-mno-thumb)
* RPM architecture name: "armv7tnhl" * ARMv7 architecture (-march=armv7-a) * NEON allowed (-mfpu=neon) * Thumb2 instruction set allowed (-mthumb)
* RPM architecture name: "armv7nhl" * ARMv7 architecture (-march=armv7-a) * NEON allowed (-mfpu=neon) * Thumb2 instruction set not used (-mno-thumb)
ARM Packages compiled in MeeGo Release 1.2 are not binary compatible with those packages that are compiled using gcc-option -mfloat-abi=softfp in MeeGo Release 1.0 or 1.1. So all the packages from Release 1.0 or 1.1 must be re-compiled using the toolchain of MeeGo 1.2.
All hardfp related issues are tracked in the metabug #11429 (http://bugs.meego.com/showdependencytree.cgi?id=11429&hide_resolved=0)