-------- Original Message -------- Subject: GCC 4.5.0 Released Date: Sun, 18 Apr 2010 16:01:49 -0700 (PDT) From: mitchell@codesourcery.com (Mark Mitchell) Reply-To: mark@codesourcery.com To: gcc-announce@gcc.gnu.org CC: gcc@gcc.gnu.org

The Free Software Foundation and the GNU Compiler Collection (GCC) development team have released GCC 4.5.0. This release is a major upgrade to the compilers, with a particular focus on the performance of the generated code. The developers have measured performance improvements of 5% to 10% on high-performance computing benchmarks. (Of course, results vary depending on choice of CPU, benchmark, and optimization options.)

GCC 4.5.0 is now capable of "link-time optimization". Traditionally, most C and C++ compilers (including GCC) have only been able to optimize within a single source file or "module". GCC was therefore unable to take advantage of optimization opportunities that required knowledge about multiple modules. This limitation has been removed in GCC 4.5.0. This optimization can provide significant increases in performance and equally significant reductions in code size.

In addition, GCC 4.5.0 has improved loop optimization infrastructure. This infrastructure, based on an advanced "polyhedral" model for optimization, allows GCC to perform more advanced loop optimizations. In the future, this infrastructure will be tuned and used more heavily.

GCC 4.5.0 also features improvements for a wide variety of specific architectures, including support for recent CPUs using the ARM, AVR, ColdFire, MIPS, Power, SuperH, and x86 architectures. GCC also generates better debug information for optimized code, including information about the value of variables that have been optimized away. And, of course, a wide variety of defects in all parts of the compiler (ranging from language conformance to code-generation) have been corrected.

Refer to gcc.gnu.org:

http://gcc.gnu.org/gcc-4.5/changes.html

for more information about this release.

GCC 4.5.1, with corrections for any critical defects reported in GCC 4.5.0, is expected in July, 2010.

As always, a vast number of people contributed to this GCC release -- far too many to thank individually!

-- Mark Mitchell CodeSourcery mark@codesourcery.com (650) 331-3385 x713