balazske added a comment.
In D75682#1917257 <https://reviews.llvm.org/D75682#1917257>, @Szelethus wrote:
> Could you please add the warning we discussed? That would be a great
> demonstration of this patch's capabilities, and wouldn't deserve its own
> patch.
Was it this warning?
if (feof(F)) { // note: Assuming the condition is true
// note: Stream 'F' has the EOF flag set
fgets(F); // warning: Illegal stream operation on a stream that has EOF set
}
The checker does not work by "assuming feof is true" (this can be a later
feature, if the `F` is not tracked and a feof call is encountered). Value of
`feof` (more precisely: if any error happened) is fixed when the file operation
is called that causes the error. The warning above should be get even if the
`feof` call is missing because it is still possible that the previous operation
resulted in EOF state. Adding a similar warning is not a small change and the
"infrastructure" for it is not ready in this revision. And still that warning
would not be testable because `FEof` error state is never set in this patch. By
the way, a file read is not invalid if any error is there, it simply fails
again. But there is many possibility for warnings such as "file read called in
EOF state", "feof called when it is proven to be false/true", "invalid file
read/write after failed fseek/fread/fwrite" but these belong to next revisions.
Probably it would be better to make a full working prototype first, because the
design decisions made now can turn out to be wrong later when the new
functionality would be added and we do "not see the full picture" now.
Repository:
rG LLVM Github Monorepo
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D75682/new/
https://reviews.llvm.org/D75682
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
