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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Michel Talon <talon@lpthe.jussieu.fr>
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Cc: David Brodbeck <gull@gull.us>,
	FreeBSD Questions <freebsd-questions@freebsd.org>
Subject: Re: Why Clang
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> lilas% clang -v
> Apple clang version 2.1 (tags/Apple/clang-163.7.1) (based on LLVM 3.0svn)
> Target: x86_64-apple-darwin11.4.0
> lilas% clang -O4 test.c -lf2c
> lilas% time ./a.out
> ...
> 
> real 0m2.359s
> user 0m2.341s
> sys 0m0.003s
> 
> lilas% /usr/local/bin/gcc -v
> ?
> gcc version 4.6.1 (GCC)
> 
> lilas% /usr/local/bin/gcc -O3 test.c -lf2c
> lilas% time ./a.out
> ?
> 
> real 0m1.241s
> user 0m1.234s
> sys 0m0.003s

So gcc actually improved.

Can you compare the execution speed of latest gcc vs. latest clang. thank 
you

i compared FReeBSD 9 supplied gcc with FreeBSD 9 supplied clang.