Which free C compiler gives options for greater optimizations?

Can you please give me some comparison between C compilers especially with respec开发者_开发知识库t to optimization?

Actually there aren't many free compilers around. gcc is "the" free compiler and probably one of the best when it comes to optimisation, even when compared to proprietary compilers.

Some independent benchmarks are linked from here: http://gcc.gnu.org/benchmarks/

I believe Intel allows you to use its ICC compilers under Linux for non-commercial development for free. ICC beats gcc and Visual Studio hands down when it comes to code generation for x86 and x86-64 (i.e. it typically generates faster code, and can do a decent job of auto-vectorization (SIMD) in some cases).

This is a hard question to answer since you did not tell us what platform you are using, neither hardware or os....

But joemoe is right, gcc tend to excel in this field.

(As a side note: On some platforms there are commercial compilers that are better, but since you gain so much more that just the compiler gcc is hard to beat...)

the Windows SDK is a free download. it includes current versions of the Visual C++ compilers. These compilers do a very good job of optimisation.