statements don't end up in the LabelMap so we don't have a quick way
to filter them. We could add state to Sema (a "has vla" and "has
jump" bit) to try to filter this out, but that would be sort of gross
and I'm not convinced it is the best way. Thoughts welcome.
llvm-svn: 69476
specific bad case instead of on the switch. Putting it on the
switch means you don't know what case is the problem. For
example:
scope-check.c:54:3: error: illegal switch case into protected scope
case 2:
^
scope-check.c:53:9: note: jump bypasses initialization of variable length array
int a[x];
^
llvm-svn: 69462
produce better diagnostics, and be more correct in ObjC cases (fixing
rdar://6803963).
An example is that we now diagnose:
int test1(int x) {
goto L;
int a[x];
int b[x];
L:
return sizeof a;
}
with:
scope-check.c:15:3: error: illegal goto into protected scope
goto L;
^
scope-check.c:17:7: note: scope created by variable length array
int b[x];
^
scope-check.c:16:7: note: scope created by variable length array
int a[x];
^
instead of just saying "invalid jump". An ObjC example is:
void test1() {
goto L;
@try {
L: ;
} @finally {
}
}
t.m:6:3: error: illegal goto into protected scope
goto L;
^
t.m:7:3: note: scope created by @try block
@try {
^
There are a whole ton of fixme's for stuff to do, but I believe that this
is a monotonic improvement over what we had.
llvm-svn: 69437
As far as I know, this catches all cases of jumping into the scope of a
variable with a variably modified type (excluding statement
expressions) in C. This is missing some stuff we probably want to check
(other kinds of variably modified declarations, statement expressions,
indirect gotos/addresses of labels in a scope, ObjC @try/@finally, cleanup
attribute), the diagnostics aren't very good, and it's not particularly
efficient, but it's a decent start.
This patch is a slightly modified version of the patch I attached to
PR3259, and it fixes that bug. I was sort of planning on improving
it, but I think it's okay as-is, especially since it looks like CodeGen
doesn't have any use for this sort of data structure. The only
significant change I can think of from the version I attached to PR3259
is that this version skips running the checking code when a function
doesn't contain any labels.
This patch doesn't cover case statements, which also need similar
checking; I'm not sure how we should deal with that. Extending the goto
checking to also check case statements wouldn't be too hard; it's just a
matter of keeping track of the scope of the closest switch and checking that
the scope of every case is the same as the scope of the switch. That said,
it would likely be a performance hit to run this check on every
function (it's an extra pass over the entire function), so we probably want
some other solution.
llvm-svn: 65678
Chris Lattner