-fno-strict-aliasing in CWARNFLAGS?

Colin Harrison colin.harrison at virgin.net
Wed Feb 3 02:15:09 PST 2010


Michel Dänzer wrote:

> Traditionally, -fno-strict-aliasing was definitely necessary for the X
> server and/or some drivers to work correctly.

Strict aliasing used to be a can'o worms...


and last time I tried strict aliasing for Xming (many moons ago) I fell flat
on my face.

But is series 4 gcc now much better? We shall see (I'm testing with libX11
and libXt unchanged; but
everything else ...most X.Org libs, most clients, pixman, Mesa and
xserver... with strict aliasing)
BTW I use -Os optimisation for all except -O2 for pixman and don't build any
xserver drivers.
So far I can't see any problems (famous last words, as they will be very

Colin Harrison

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