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Full Discussion: realloc fails in C : what next ?
Top Forums Programming realloc fails in C : what next ? Post 302457558 by kermit on Tuesday 28th of September 2010 09:25:11 AM
Old 09-28-2010
Quote:
Originally Posted by jossojjos
I used the makefile that came with the software, which adds these options to the gcc command :
CFLAGS = -O4 -funroll-loops -fomit-frame-pointer -finline-functions
As an aside, whoever wrote the makefile was trying to be really aggressive with the optimizations. Perhaps they were using bad algorithms to start with, and thought to speed things up by cranking up the compiler optimizations. At any rate, these optimizing switches sometimes do, but sometimes don't, speed up execution time. Only a careful analysis (profiling) can provide the answer. At any rate, GCC offers up to -O3. -O4 is not an option, to my knowledge.
 

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cfspeed(3C)															       cfspeed(3C)

NAME

       cfgetospeed(), cfsetospeed(), cfgetispeed(), cfsetispeed() - tty baud rate functions

SYNOPSIS

DESCRIPTION

       These  functions set and get the input and output speed codes in the termios structure referenced by termios_p.	The termios structure con-
       tains these speed codes representing input and output baud rates as well as other terminal related parameters.  Setting the parameters on a
       terminal file does not become effective until is successfully called.

	      returns the output speed code from the
				  termios structure referenced by termios_p.

	      sets the output speed code in the
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RETURN VALUE

       returns the output speed code from the termios structure referenced by termios_p.

       returns the input speed code from the termios structure referenced by termios_p.

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ERRORS

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WARNINGS

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SEE ALSO

       tcattribute(3C), thread_safety(5), termio(7).

STANDARDS CONFORMANCE

																       cfspeed(3C)
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