On Wed, Feb 24, 2016 at 10:15:35AM -0500, Jason Merrill wrote: > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -6809,7 +6809,10 @@ value, and any changes during the lifetime of the > object are dead when > the object is destroyed. Normally dead store elimination will take > advantage of this; if your code relies on the value of the object > storage persisting beyond the lifetime of the object, you can use this > -flag to disable this optimization. > +flag to disable this optimization. To preserve stores before the > +constructor starts (e.g. because your operator new clears the object > +storage) but still treat the object as dead after the destructor you, > +can use -flifetime-dse=1.
That should be @option{-flifetime-dse=1} I think. Shouldn't -flifetime-dse= be also in @opindex at the beginning of the paragraph, and documented what the values mean (0 equivalent of -fno-lifetime-dse (or document it vice versa) and 2 full lifetime dse enabled? Jakub