Draft 2012.08 Release Notes

The Linaro Toolchain Working Group is pleased to announce the 2012.08 release of both Linaro GCC 4.7 and Linaro GCC 4.6.

Linaro GCC 4.7 2012.08 is the fifth release in the 4.7 series. Based off the latest GCC 4.7.1+svn189992 release, it includes many ARM-focused performance improvements and bug fixes.

Interesting changes include:

  • Updates to GCC 4.7.1+svn189992
  • An ABI fix for vectors with the wrong layout
  • Backports improvements to the NEON vdup instruction with immediates
  • Backports a fix to performance regressions in partial redundancy elimination at high optimisation
  • Backports faster 64 bit core register adds with immediates

A bug has been fixed in GCC's implementation of the AAPCS rules for the layout of vectors that could lead to wrong code being generated. Vectors larger than 8 bytes in size are now by default aligned to an 8-byte boundary. This is an ABI change: code that makes explicit use of vector types may be incompatible with binary objects built with older versions of GCC. Auto-vectorized code is not affected by this change.

Fixes:

  • LP: #1020601 Strange behaviour with builtin_unreachable()

  • PR38785 huge performance regression on EEMBC bitmnp01
  • PR53447 missed optimization of 64bit ALU operation with small constant

Linaro GCC 4.6 2012.08 is the eighteenth release in the 4.6 series. Based off the latest GCC 4.6.3+svn189991 release, this is the fifth release after entering maintenance.

Interesting changes include:

  • Updates to 4.6.3+svn189991
  • An ABI fix for vectors with the wrong layout

A bug has been fixed in GCC's implementation of the AAPCS rules for the layout of vectors that could lead to wrong code being generated. Vectors larger than 8 bytes in size are now by default aligned to an 8-byte boundary. This is an ABI change: code that makes explicit use of vector types may be incompatible with binary objects built with older versions of GCC. Auto-vectorized code is not affected by this change.

The source tarballs are available from:

Downloads are available from the Linaro GCC page on Launchpad:

More information on the features and issues are available from the release page:

Mailing list: http://lists.linaro.org/mailman/listinfo/linaro-toolchain

Bugs: https://bugs.launchpad.net/gcc-linaro/

Questions? https://ask.linaro.org/

Interested in commercial support? Inquire at support@linaro.org

WorkingGroups/ToolChain/GCC/ReleaseNotes/GCC2012.08ReleaseNotes (last modified 2012-10-22 20:17:25)