◄Up► ◄Contents► ◄Index► ◄Back► ─────C/C++ Compiler───────────────────────────────────────────────────────── Syntax: /O[opt_code] These options affect the behavior of loop optimization: Option Compiler Action /Ol Causes the compiler to perform loop optimization by moving invariant code out of loops. /Oz Enables maximum, and potentially unsafe, loop optimization. /On Disables unsafe loop optimizations by preventing some constant expressions in a loop from being moved out. Since the /Ol option automatically implies /On, you do not need to specify /On explicitly; it is provided for compatibility with earlier versions of Microsoft C. The /Oz option aggressively removes as many invariant expressions as possible from a loop. If you do not specify /Oz, the /Ol option removes only the invariant expressions guaranteed to be executed in every iteration of the loop. Do not use /Oz if you suspect a loop optimization has caused an error. NOTES: ■ If /Ol is given with the /Os (Optimize for Size) option, the effect of /Ol takes precedence for loops. ■ If you specify /On without /Ol, /On has no effect. The /On option only works when it is specified with /Ol. -♦-