Hi -
> What I'm wondering is whether or not mudflap should instrument accesses
> to globals that it doesn't know the size of. In the following code:
> [...]
> printf("%d\n", global[3]);
> [...] Mudflap does not emit any __mf_check calls.
It is probably kicking in an optimization that says that if the
indexes are literals and thus statically checkable against array
bounds, then there is no need for a runtime check. The problem here
is of course that we can't do the static check after all because of
the extern[]. There is also another complication (unhelpful
TREE_ADDRESSABLE flag setting for this and a few other cases).
> [...] I'd much prefer if it did go on and check all accesses to the
> array because in my case, global[] will always be registered by the
> compilation unit in which it is defined. [...]
On the other hand, mudflap can't know that this extern[] will be
registered by that other compilation unit, since that might be
compiled without -fmudflap. An mf_check against it would then fail.
- FChE
