https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57612
felix <felix.von.s at posteo dot de> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |felix.von.s at posteo dot de
--- Comment #3 from felix <felix.von.s at posteo dot de> ---
Overlaps bug 6906. Under that ticket, I proposed adding a built-in that simply
returns whether or not a given expression has side effects, simply by exposing
TREE_SIDE_EFFECTS(). This more general built-in could also (partially) address
bug 79469, by allowing to define __builtin_assume as
#define __builtin_assume(cond) do { \
if (__builtin_pure_p(cond)) \
if (!(cond)) \
__builtin_unreachable(); \
} while (0)
Partially, because e.g. if A has side effects, then with the definition above
__builtin_assume(A && B) would consider the whole condition to have side
effects as well, and therefore disregard it, even if B could potentially be
mined for optimisation opportunities.
